diff --git a/transfer_service/db_connector.py b/transfer_service/db_connector.py
index 824cdae9955951de6b3bafee3d16e09f8c5f5320..53b4346b025a86b0b8c1f77ee4cf88ffddbdbaee 100644
--- a/transfer_service/db_connector.py
+++ b/transfer_service/db_connector.py
@@ -58,14 +58,15 @@ class DbConnector(object):
                 cursor = conn.cursor(cursor_factory = RealDictCursor)
                 cursor.execute("SELECT * FROM node_vos_path WHERE vos_path = %s;", (vospacePath,))
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-                print(e)
-        if result:
-            return True
-        else:
-            return False
+                raise
+            else:
+                if result:
+                    return True
+                else:
+                    return False
 
     def getCreatorId(self, vospacePath):
         """Returns the creator ID for a given vospace path representing a node."""
@@ -80,11 +81,12 @@ class DbConnector(object):
                     """, 
                     (vospacePath,))
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-                print(e)
-        return result[0]["creator_id"]
+                raise
+            else:
+                return result[0]["creator_id"]
 
     def getGroupRead(self, vospacePath):
         """Returns the 'group_read' for a given VOSpace path representing a node."""
@@ -99,13 +101,14 @@ class DbConnector(object):
                     """, 
                     (vospacePath,))
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-                print(e)
-        for i in range(0, len(result)):
-            result[i]["group_read"] = result[i]["group_read"].split("people.")[-1].replace("\\", "")
-        return result
+                raise
+            else:
+                for i in range(0, len(result)):
+                    result[i]["group_read"] = result[i]["group_read"].split("people.")[-1].replace("\\", "")
+                return result
 
     def getGroupWrite(self, vospacePath):
         """Returns the 'group_write' for a given VOSpace path representing a node."""
@@ -120,13 +123,14 @@ class DbConnector(object):
                     """, 
                     (vospacePath,))
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-                print(e)
-        for i in range(0, len(result)):
-            result[i]["group_write"] = result[i]["group_write"].split("people.")[-1].replace("\\", "")
-        return result
+                raise
+            else:
+                for i in range(0, len(result)):
+                    result[i]["group_write"] = result[i]["group_write"].split("people.")[-1].replace("\\", "")
+                return result
 
     def getOSPath(self, vospacePath):
         """Returns a list containing full path, storage type and username for a VOSpace path."""
@@ -143,30 +147,31 @@ class DbConnector(object):
                     """,
                     (vospacePath,))
                 result = cursor.fetchall()
-            except Exception as e:
-                if not conn.closed:
-                    conn.rollback()
-                print(e)
-        storageType = result[0]["storage_type"]
-        basePath = result[0]["base_path"]
-        userName = result[0]["user_name"]
-        tstampWrappedDir = result[0]["tstamp_wrapper_dir"]
-        osPath = result[0]["os_path"]
-        contentLength = result[0]["content_length"]
-        if tstampWrappedDir is None:
-            baseSrcPath = basePath + "/" + userName
-        else:
-            baseSrcPath = basePath + "/" + userName + "/" + tstampWrappedDir
-        fullPath = baseSrcPath + osPath
-        fileInfo = {
-                       "baseSrcPath": baseSrcPath,
-                       "fullPath": fullPath, 
-                       "storageType": storageType, 
-                       "username": userName, 
-                       "osPath": osPath,
-                       "contentLength": contentLength
-                   }
-        return fileInfo
+            except Exception:
+                if not conn.closed:
+                    conn.rollback()
+                raise
+            else:
+                storageType = result[0]["storage_type"]
+                basePath = result[0]["base_path"]
+                userName = result[0]["user_name"]
+                tstampWrappedDir = result[0]["tstamp_wrapper_dir"]
+                osPath = result[0]["os_path"]
+                contentLength = result[0]["content_length"]
+                if tstampWrappedDir is None:
+                    baseSrcPath = basePath + "/" + userName
+                else:
+                    baseSrcPath = basePath + "/" + userName + "/" + tstampWrappedDir
+                fullPath = baseSrcPath + osPath
+                fileInfo = {
+                               "baseSrcPath": baseSrcPath,
+                               "fullPath": fullPath, 
+                               "storageType": storageType, 
+                               "username": userName, 
+                               "osPath": osPath,
+                               "contentLength": contentLength
+                          }
+                return fileInfo
 
     def getVOSpacePathList(self, vospacePath):
         """Returns the list of VOSpace paths carried by a VOSpace node, according to the node VOSpace path."""
@@ -181,14 +186,15 @@ class DbConnector(object):
                     """,
                     (vospacePath,))
                 results = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-                print(e)
-        vospacePathList = []
-        for el in results:
-            vospacePathList.append(el["vos_path"])
-        return vospacePathList
+                raise
+            else:
+                vospacePathList = []
+                for el in results:
+                    vospacePathList.append(el["vos_path"])
+                return vospacePathList
 
     def getNodesToBeDeleted(self):
         "Returns a path list of files to be deleted with also the corresponding deletion timestamp."
@@ -221,11 +227,12 @@ class DbConnector(object):
                     JOIN storage s ON s.storage_id = l.storage_src_id;
                     """)
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-                print(e)
-        return result
+                raise
+            else:
+                return result
 
     def nodeIsBusy(self, vospacePath):
         """Returns 'True' if the VOSpace node is busy, 'False' otherwise."""
@@ -239,14 +246,15 @@ class DbConnector(object):
                     """,
                     (vospacePath,))
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-                print(e)
-        if result[0]["job_id"]:
-            return True
-        else:
-            return False
+                raise
+            else:
+                if result[0]["job_id"]:
+                    return True
+                else:
+                    return False
 
     ##### Job #####
 
@@ -257,14 +265,15 @@ class DbConnector(object):
                 cursor = conn.cursor(cursor_factory = RealDictCursor)
                 cursor.execute("SELECT * FROM job WHERE job_id = %s;", (jobId,))
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-                print(e)
-        if result:
-            return True
-        else:
-            return False
+                raise
+            else:
+                if result:
+                    return True
+                else:
+                    return False
 
     def getJob(self, jobId):
         """Returns a JSON object containing job information, according to the job id."""
@@ -276,24 +285,26 @@ class DbConnector(object):
                 result = cursor.fetchall()
                 #out.write(f"result: {result}\n\n")
                 #out.close()
-            except Exception as e:
-                if not conn.closed:
-                    conn.rollback()
-        if not result:
-            return json.loads('{ "error": "JOB_NOT_FOUND" }')
-        else:
-            job = dict()
-            for idx in result[0]:
-                oldIdx = idx
-                idxTokens = idx.split('_')
-                idx = idxTokens[0] + ''.join(token.title() for token in idxTokens[1:])
-                job[idx] = result[0][oldIdx]
-                el = job[idx]
-                if isinstance(el, datetime.datetime):
-                    job[idx] = el.isoformat()
-            #out.write(f"job: {job}\n\n")
-            #out.close()
-            return job
+            except Exception:
+                if not conn.closed:
+                    conn.rollback()
+                raise
+            else:
+                if not result:
+                    return json.loads('{ "error": "JOB_NOT_FOUND" }')
+                else:
+                    job = dict()
+                    for idx in result[0]:
+                        oldIdx = idx
+                        idxTokens = idx.split('_')
+                        idx = idxTokens[0] + ''.join(token.title() for token in idxTokens[1:])
+                        job[idx] = result[0][oldIdx]
+                        el = job[idx]
+                        if isinstance(el, datetime.datetime):
+                            job[idx] = el.isoformat()
+                    #out.write(f"job: {job}\n\n")
+                    #out.close()
+                    return job
 
     def getJobInfo(self, jobId):
         """Returns the 'job_info' field, according to the UWS specification."""
@@ -302,10 +313,12 @@ class DbConnector(object):
                 cursor = conn.cursor(cursor_factory = RealDictCursor)
                 cursor.execute("SELECT job_info FROM job WHERE job_id = %s;", (jobId,))
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-        return result[0]["job_info"]
+                raise
+            else:
+                return result[0]["job_info"]
 
     def getJobResults(self, jobId):
         """Returns the 'results' field, according to the UWS specification."""
@@ -314,10 +327,12 @@ class DbConnector(object):
                 cursor = conn.cursor(cursor_factory = RealDictCursor)
                 cursor.execute("SELECT results FROM job WHERE job_id = %s;", (jobId,))
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-        return result[0]["results"]
+                raise
+            else:
+                return result[0]["results"]
 
     def listActiveJobs(self):
         """Returns some info about active jobs."""
@@ -339,15 +354,17 @@ class DbConnector(object):
                            ORDER BY creation_time DESC;
                     """)
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-        for row in result:
-            for idx in row:
-                el = row[idx]
-                if isinstance(el, datetime.datetime):
-                    row[idx] = el.isoformat()
-        return result
+                raise
+            else:
+                for row in result:
+                    for idx in row:
+                        el = row[idx]
+                        if isinstance(el, datetime.datetime):
+                            row[idx] = el.isoformat()
+                return result
 
     def listJobsByPhase(self, phase):
         """Returns some info about jobs according to the phase."""
@@ -381,15 +398,17 @@ class DbConnector(object):
                         """,
                         (phase,))
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-        for row in result:
-            for idx in row:
-                el = row[idx]
-                if isinstance(el, datetime.datetime):
-                    row[idx] = el.isoformat()
-        return result
+                raise
+            else:
+                for row in result:
+                    for idx in row:
+                        el = row[idx]
+                        if isinstance(el, datetime.datetime):
+                            row[idx] = el.isoformat()
+                return result
 
     ##### User #####
 
@@ -400,13 +419,15 @@ class DbConnector(object):
                 cursor = conn.cursor(cursor_factory = RealDictCursor)
                 cursor.execute("SELECT * FROM users WHERE user_name = %s;", (username,))
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-        if result:
-            return True
-        else:
-            return False
+                raise
+            else:
+                if result:
+                    return True
+                else:
+                    return False
 
     def getUserId(self, username):
         """Returns the user id for a given user name."""
@@ -415,10 +436,12 @@ class DbConnector(object):
                 cursor = conn.cursor(cursor_factory = RealDictCursor)
                 cursor.execute("SELECT user_id FROM users WHERE user_name = %s;", (username,))
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-        return result[0]["user_id"]
+                raise
+            else:
+                return result[0]["user_id"]
 
     def getUserName(self, userId):
         """Returns the user name for a given user id."""
@@ -427,10 +450,12 @@ class DbConnector(object):
                 cursor = conn.cursor(cursor_factory = RealDictCursor)
                 cursor.execute("SELECT user_name FROM users WHERE user_id = %s;", (userId,))
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-        return result[0]["user_name"]
+                raise
+            else:
+                return result[0]["user_name"]
     
     def getUserEmail(self, userId):
         """Returns the user email address for a given user id."""
@@ -439,10 +464,12 @@ class DbConnector(object):
                 cursor = conn.cursor(cursor_factory = RealDictCursor)
                 cursor.execute("SELECT e_mail FROM users WHERE user_id = %s;", (userId,))
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-        return result[0]["e_mail"]
+                raise
+            else:
+                return result[0]["e_mail"]
 
     ##### Storage #####
 
@@ -458,13 +485,15 @@ class DbConnector(object):
                     """,
                     (path,))
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-        if result:
-            return result[0]["base_path"]
-        else:
-            return False
+                raise
+            else:
+                if result:
+                    return result[0]["base_path"]
+                else:
+                    return False
 
     def getStorageBasePath(self, storageId):
         """Returns the storage base path for a give storage id."""
@@ -473,10 +502,12 @@ class DbConnector(object):
                 cursor = conn.cursor(cursor_factory = RealDictCursor)
                 cursor.execute("SELECT base_path FROM storage WHERE storage_id = %s;", (storageId,))
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-        return result[0]["base_path"]
+                raise
+            else:
+                return result[0]["base_path"]
 
     def getStorageList(self):
         """Returns the full storage base list. Local storage points are excluded by default."""
@@ -485,10 +516,12 @@ class DbConnector(object):
                 cursor = conn.cursor(cursor_factory = RealDictCursor)
                 cursor.execute("SELECT * FROM storage WHERE storage_type <> 'local';")
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-        return result
+                raise
+            else:
+                return result
 
     def getStorageListByType(self, storageType):
         """Returns a list of storage locations for a given storage type."""
@@ -497,10 +530,12 @@ class DbConnector(object):
                 cursor = conn.cursor(cursor_factory = RealDictCursor)
                 cursor.execute("SELECT * FROM storage WHERE storage_type = %s;", (storageType,))
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-        return result
+                raise
+            else:
+                return result
 
     def getStorageType(self, basePath):
         """Returns the storage type for a given storage base path, if any. Otherwise it returns 'False'."""
@@ -509,13 +544,15 @@ class DbConnector(object):
                 cursor = conn.cursor(cursor_factory = RealDictCursor)
                 cursor.execute("SELECT storage_type FROM storage WHERE base_path = %s;", (basePath,))
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-        if result:
-            return result[0]["storage_type"]
-        else:
-            return False
+                raise
+            else:
+                if result:
+                    return result[0]["storage_type"]
+                else:
+                    return False
 
     def getStorageId(self, basePath):
         """Returns the storage id for a given storage base path, if any. Otherwise it returns 'False'."""
@@ -524,13 +561,15 @@ class DbConnector(object):
                 cursor = conn.cursor(cursor_factory = RealDictCursor)
                 cursor.execute("SELECT storage_id FROM storage WHERE base_path = %s;", (basePath,))
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-        if result:
-            return result[0]["storage_id"]
-        else:
-            return False
+                raise
+            else:
+                if result:
+                    return result[0]["storage_id"]
+                else:
+                    return False
 
     ##### Location #####
 
@@ -541,10 +580,12 @@ class DbConnector(object):
                 cursor = conn.cursor(cursor_factory = RealDictCursor)
                 cursor.execute("SELECT location_id FROM location WHERE storage_src_id = %s;", (destStorageId,))
                 result = cursor.fetchall()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-        return result[0]["location_id"]
+                raise
+            else:
+                return result[0]["location_id"]
 
 
     """
@@ -602,9 +643,10 @@ class DbConnector(object):
                      jobObj.errorMessage,
                      jobObj.errorType,))
                 conn.commit()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
+                raise
             
     def setStartTime(self, jobId):
         """Sets the job 'start_time' parameter."""
@@ -618,9 +660,10 @@ class DbConnector(object):
                     """,
                     (startTime, jobId,))
                 conn.commit()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
+                raise
  
     def setEndTime(self, jobId):
         """Sets the job 'end_time' parameter."""
@@ -634,9 +677,10 @@ class DbConnector(object):
                     """,
                     (endTime, jobId,))
                 conn.commit()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
+                raise
 
     def setPhase(self, jobId, phase):
         """Sets the job 'phase' parameter."""
@@ -649,9 +693,10 @@ class DbConnector(object):
                     """,
                     (phase, jobId,))
                 conn.commit()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
+                raise
                     
     def setTotalBlocks(self, jobId, totalBlocks):
         """
@@ -667,9 +712,10 @@ class DbConnector(object):
                     """,
                     (totalBlocks, jobId,))
                 conn.commit()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
+                raise
                     
     def updateProcessedBlocks(self, jobId, processedBlocks):
         """
@@ -685,9 +731,10 @@ class DbConnector(object):
                     """,
                     (processedBlocks, jobId,))
                 conn.commit()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
+                raise
 
     def setResults(self, jobId, results):
         """Sets the job 'results' parameter."""
@@ -701,9 +748,10 @@ class DbConnector(object):
                     (json.dumps(results),
                      jobId,))
                 conn.commit()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
+                raise
 
     ##### Node #####
 
@@ -730,51 +778,54 @@ class DbConnector(object):
                 #out.write(f"parentLtreePath: {parentLtreePath}\n")
                 #out.write(f"parentPath: {node.parentPath}\n\n")
                 #out.close()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-                    
-            try:
-                #print(f"parentLtreePath: {parentLtreePath}, type: {type(parentLtreePath)}")
-                cursor.execute("""
-                    INSERT INTO node(parent_path,
-                                     parent_relative_path,
-                                     name,
-                                     tstamp_wrapper_dir,
-                                     type,
-                                     location_id,
-                                     async_trans,
-                                     sticky,
-                                     job_id,
-                                     creator_id,
-                                     content_length,
-                                     content_md5)
-                    VALUES (%s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s)
-                    ON CONFLICT
-                    DO NOTHING
-                    RETURNING node_id;
-                    """,
-                    (parentLtreePath,
-                     parentLtreeRelativePath,
-                     node.name,
-                     node.wrapperDir,
-                     node.type,
-                     node.locationId,
-                     node.asyncTrans,
-                     node.sticky,
-                     node.jobId,
-                     node.creatorId,
-                     node.contentLength,
-                     node.contentMD5,))
-                result = cursor.fetchall()
-                conn.commit()
-                if result:
-                    return True
+                raise
+            else:        
+                try:
+                    #print(f"parentLtreePath: {parentLtreePath}, type: {type(parentLtreePath)}")
+                    cursor.execute("""
+                        INSERT INTO node(parent_path,
+                                         parent_relative_path,
+                                         name,
+                                         tstamp_wrapper_dir,
+                                         type,
+                                         location_id,
+                                         async_trans,
+                                         sticky,
+                                         job_id,
+                                         creator_id,
+                                         content_length,
+                                         content_md5)
+                        VALUES (%s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s)
+                        ON CONFLICT
+                        DO NOTHING
+                        RETURNING node_id;
+                        """,
+                        (parentLtreePath,
+                         parentLtreeRelativePath,
+                         node.name,
+                         node.wrapperDir,
+                         node.type,
+                         node.locationId,
+                         node.asyncTrans,
+                         node.sticky,
+                         node.jobId,
+                         node.creatorId,
+                         node.contentLength,
+                         node.contentMD5,))
+                    result = cursor.fetchall()
+                    conn.commit()                    
+                except Exception:
+                    if not conn.closed:
+                        conn.rollback()
+                    raise
                 else:
-                    return False
-            except Exception as e:
-                if not conn.closed:
-                    conn.rollback()
+                    if result:
+                        return True
+                    else:
+                        return False
 
     def setAsyncTrans(self, nodeVOSPath, value):
         """Sets the 'async_trans' flag for a VOSpace node."""
@@ -788,9 +839,10 @@ class DbConnector(object):
                     """,
                     (value, nodeVOSPath,))
                 conn.commit()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
+                raise
 
     def setJobId(self, nodeVOSPath, value):
         """Sets the 'job_id' flag for a VOSpace node."""
@@ -804,9 +856,10 @@ class DbConnector(object):
                     """,
                     (value, nodeVOSPath,))
                 conn.commit()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
+                raise
                     
     def setPhyDeletedOn(self, nodeId):
         """Sets the 'phy_deleted_on' flag for a VOSpace deleted node."""
@@ -820,9 +873,10 @@ class DbConnector(object):
                     """,
                     (phyDeletedOn, nodeId,))
                 conn.commit()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
+                raise
                     
     def updateGroupRead(self, groupToAdd, groupToRemove, nodeVOSPath):
         with self.getConnection() as conn:
@@ -838,9 +892,10 @@ class DbConnector(object):
                      groupToRemove,
                      nodeVOSPath,))
                 conn.commit()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
+                raise
                     
     def updateGroupWrite(self, groupToAdd, groupToRemove, nodeVOSPath):
         with self.getConnection() as conn:
@@ -856,9 +911,10 @@ class DbConnector(object):
                      groupToRemove,
                      nodeVOSPath,))
                 conn.commit()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
+                raise
 
     ##### Storage #####
 
@@ -880,46 +936,48 @@ class DbConnector(object):
                          basePath,
                          baseUrl,
                          hostname,))
-
                     storageSrcId = cursor.fetchall()[0]["storage_id"]
-
-                except Exception as e:
+                except Exception:
                     if not conn.closed:
                         conn.rollback()
-
-                if storageType == "cold" or storageType == "hot":
+                    raise
+                else:
+                    if storageType == "cold" or storageType == "hot":
+                        try:
+                            cursor.execute("""
+                                SELECT storage_id
+                                FROM storage
+                                WHERE storage_type = 'local'
+                                AND base_path = '/home'
+                                AND hostname = 'localhost';
+                                """)
+                            storageDestId = cursor.fetchall()[0]["storage_id"]
+                        except Exception:
+                            if not conn.closed:
+                                conn.rollback()
+                            raise
+                        else:
+                            locationType = "async"
+                    else:
+                        storageDestId = storageSrcId
+                        locationType = "portal"
                     try:
                         cursor.execute("""
-                            SELECT storage_id
-                            FROM storage
-                            WHERE storage_type = 'local'
-                            AND base_path = '/home'
-                            AND hostname = 'localhost';
-                            """)
-                        storageDestId = cursor.fetchall()[0]["storage_id"]
-                    except Exception as e:
+                            INSERT INTO location(location_type,
+                                                 storage_src_id,
+                                                 storage_dest_id)
+                            VALUES (%s, %s, %s);
+                            """,
+                            (locationType,
+                             storageSrcId,
+                             storageDestId,))
+                        conn.commit()
+                    except Exception:
                         if not conn.closed:
                             conn.rollback()
-                    locationType = "async"
-                else:
-                    storageDestId = storageSrcId
-                    locationType = "portal"
-                try:
-                    cursor.execute("""
-                        INSERT INTO location(location_type,
-                                             storage_src_id,
-                                             storage_dest_id)
-                        VALUES (%s, %s, %s);
-                        """,
-                        (locationType,
-                         storageSrcId,
-                         storageDestId,))
-
-                    conn.commit()
-                except:
-                    if not conn.closed:
-                        conn.rollback()
-                return True
+                        raise
+                    else:
+                        return True
             else:
                 return False
 
@@ -940,24 +998,27 @@ class DbConnector(object):
                     """,
                     (storageId,))
                 result = cursor.fetchall()
-            except:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
-
-            if result[0]["res"]:
-                return False
+                raise
             else:
-                try:
-                    cursor.execute("""
-                        DELETE FROM storage
-                        WHERE storage_id = %s;
-                        """,
-                        (storageId,))
-                    conn.commit()
-                except:
-                    if not conn.closed:
-                        conn.rollback()
-                return True
+                if result[0]["res"]:
+                    return False
+                else:
+                    try:
+                        cursor.execute("""
+                            DELETE FROM storage
+                            WHERE storage_id = %s;
+                            """,
+                            (storageId,))
+                        conn.commit()
+                    except Exception:
+                        if not conn.closed:
+                            conn.rollback()
+                        raise
+                    else:
+                        return True
 
     ##### Users #####
      
@@ -978,6 +1039,7 @@ class DbConnector(object):
                      username,
                      email,))
                 conn.commit()
-            except Exception as e:
+            except Exception:
                 if not conn.closed:
                     conn.rollback()
+                raise
diff --git a/transfer_service/exceptions.py b/transfer_service/exceptions.py
index a133d044adcd3f9739485bfe5994f7a946542eae..cf52af2bd2d73bf9db45d76edde63598097110df 100644
--- a/transfer_service/exceptions.py
+++ b/transfer_service/exceptions.py
@@ -5,7 +5,15 @@ class Error(Exception):
     pass 
 
 
-# RAP exceptions
+# FileGrouper exceptions
+
+class TarFileCreationException(Error):
+    def __init__(self, folder):
+        self.message = "Error: cannot create a .tar for " + folder
+        super(MultipleUsersException, self).__init__(self.message)
+
+
+# RapClient exceptions
 
 class MultipleUsersException(Error):
     def __init__(self):
diff --git a/transfer_service/file_grouper.py b/transfer_service/file_grouper.py
index 65435794a5fd2f0eacd61ec43c73c7b3f105f371..7f2b57fcda28be555a6f24ba504bd3f47dc37a9a 100644
--- a/transfer_service/file_grouper.py
+++ b/transfer_service/file_grouper.py
@@ -5,6 +5,8 @@ import shutil
 import subprocess
 import sys
 
+from exceptions import TarFileCreationException
+
 
 class FileGrouper(object):
 
@@ -61,7 +63,7 @@ class FileGrouper(object):
                 os.chdir(parent)
                 sp = subprocess.run(["tar", "-cf", os.path.basename(folder) + ".tar", os.path.basename(folder)], capture_output = True)
                 if(sp.returncode or sp.stderr):
-                    sys.exit(f"Error: cannot create a .tar for {folder}")
+                    raise(TarFileCreationException(folder))
                 else:
                     try:
                         shutil.rmtree(folder)
diff --git a/transfer_service/job_queue.py b/transfer_service/job_queue.py
index 8e7a96481412c6e91cc75b3ceae5ec7f0507be99..b0c61c2a4c83964204b38198ba95c503bdc97a7f 100644
--- a/transfer_service/job_queue.py
+++ b/transfer_service/job_queue.py
@@ -1,6 +1,6 @@
 #!/usr/bin/env python
 #
-# A FIFO queue based on a Redis list
+# A FIFO queue based on Redis lists
 #
 #
 
@@ -23,7 +23,12 @@ class JobQueue(object):
 
     def len(self):
         """Returns the number of jobs in the current queue."""
-        return self.redisCli.llen(self.queueName)
+        try:
+            numJobs = self.redisCli.llen(self.queueName)
+        except Exception:
+            raise
+        else:
+            return numJobs
 
     def name(self):
         """Returns the name of the current queue."""
@@ -31,18 +36,22 @@ class JobQueue(object):
 
     def getJob(self):
         """Gets a copy of the first job without moving it out from the current queue."""
-        job = json.loads(self.redisCli.lrange(self.queueName, self.len() - 1, self.len() - 1)[0].decode("utf-8"))
-        jobObj = Job()
-        jobObj.setId(job["jobId"])
-        jobObj.setType(job["jobType"])
-        jobObj.setOwnerId(job["ownerId"])
-        jobObj.setPhase(job["phase"])
-        jobObj.setQuote(job["quote"])
-        jobObj.setStartTime(job["startTime"])
-        jobObj.setEndTime(job["endTime"])
-        jobObj.setExecutionDuration(job["executionDuration"])
-        jobObj.setInfo(job["jobInfo"])
-        return jobObj
+        try:
+            job = json.loads(self.redisCli.lrange(self.queueName, self.len() - 1, self.len() - 1)[0].decode("utf-8"))
+            jobObj = Job()
+            jobObj.setId(job["jobId"])
+            jobObj.setType(job["jobType"])
+            jobObj.setOwnerId(job["ownerId"])
+            jobObj.setPhase(job["phase"])
+            jobObj.setQuote(job["quote"])
+            jobObj.setStartTime(job["startTime"])
+            jobObj.setEndTime(job["endTime"])
+            jobObj.setExecutionDuration(job["executionDuration"])
+            jobObj.setInfo(job["jobInfo"])
+        except Exception:
+            raise
+        else:
+            return jobObj
 
     def insertJob(self, jobObj):
         """Pushes a new job into the queue."""
@@ -58,22 +67,29 @@ class JobQueue(object):
                  "parameters": jobObj.parameters,
                  "results": jobObj.results,
                  "jobInfo": jobObj.jobInfo }
-        self.redisCli.lpush(self.queueName, json.dumps(data))
+        try:
+            self.redisCli.lpush(self.queueName, json.dumps(data))
+        except Exception:
+            raise
 
     def extractJob(self):
         """Moves out a job from the end of the current queue."""
-        job = json.loads(self.redisCli.brpop(self.queueName)[1].decode("utf-8"))
-        jobObj = Job()
-        jobObj.setId(job["jobId"])
-        jobObj.setType(job["jobType"])
-        jobObj.setOwnerId(job["ownerId"])
-        jobObj.setPhase(job["phase"])
-        jobObj.setQuote(job["quote"])
-        jobObj.setStartTime(job["startTime"])
-        jobObj.setEndTime(job["endTime"])
-        jobObj.setExecutionDuration(job["executionDuration"])
-        jobObj.setInfo(job["jobInfo"])
-        return jobObj
+        try:
+            job = json.loads(self.redisCli.brpop(self.queueName)[1].decode("utf-8"))
+            jobObj = Job()
+            jobObj.setId(job["jobId"])
+            jobObj.setType(job["jobType"])
+            jobObj.setOwnerId(job["ownerId"])
+            jobObj.setPhase(job["phase"])
+            jobObj.setQuote(job["quote"])
+            jobObj.setStartTime(job["startTime"])
+            jobObj.setEndTime(job["endTime"])
+            jobObj.setExecutionDuration(job["executionDuration"])
+            jobObj.setInfo(job["jobInfo"])
+        except Exception:
+            raise
+        else:
+            return jobObj
 
     def moveJobTo(self, nextQueueName):
         """
@@ -81,7 +97,10 @@ class JobQueue(object):
         at the beginning of the next queue (this operation is atomic)
         DEPRECATED
         """
-        self.redisCli.brpoplpush(self.queueName, nextQueueName)
+        try:
+            self.redisCli.brpoplpush(self.queueName, nextQueueName)
+        except Exception:
+            raise
 
 
 # Test
diff --git a/transfer_service/mailer.py b/transfer_service/mailer.py
index fbf5eb90551987fd5185a95aa06a93ac0c7d7a11..01de02afc5c61d6c06842bd59d25b8b736aa0915 100644
--- a/transfer_service/mailer.py
+++ b/transfer_service/mailer.py
@@ -63,17 +63,14 @@ class Mailer(object):
             try:
                 smtpObj = smtplib.SMTP(self.smtpServer, self.smtpPort)
                 smtpObj.send_message(self.message)
-                logMsg = "E-mail message sent successfully!"
-                self.logger.debug(logMsg)
             except SMTPConnectError:
-                logMsg = "Cannot connect to SMTP server."
-                self.logger.exception(logMsg)
+                self.logger.exception("Cannot connect to SMTP server.")
             except TimeoutError:
-                logMsg = "Connection timeout."
-                self.logger.exception(logMsg)
+                self.logger.exception("Connection timeout.")
             except SMTPException:
-                logMsg = "Cannot send email message."
-                self.logger.exception(logMsg)
+                self.logger.exception("Cannot send email message.")
+            else:
+                self.logger.debug("E-mail message sent successfully!")
         else:
             self.logger.debug("E-mail notifications disabled.")
 
diff --git a/transfer_service/redis_rpc_server.py b/transfer_service/redis_rpc_server.py
index fe59f10706546d6a72750be425920b394c17741d..39f39b500328736729f8ccd9d449a2632ff92d04 100644
--- a/transfer_service/redis_rpc_server.py
+++ b/transfer_service/redis_rpc_server.py
@@ -13,12 +13,15 @@ class RedisRPCServer(threading.Thread):
 
     def run(self):
         while True:
-            channel, request = self.client.brpop(self.rpcQueue)
-            channel = channel.decode("utf-8")
-            request = json.loads(request.decode("utf-8"))
-            response = self.callback(request)
-            self.client.rpush(request["req_id"], json.dumps(response))
-            self.client.expire(request["req_id"], 30)
+            try:
+                channel, request = self.client.brpop(self.rpcQueue)
+                channel = channel.decode("utf-8")
+                request = json.loads(request.decode("utf-8"))
+                response = self.callback(request)
+                self.client.rpush(request["req_id"], json.dumps(response))
+                self.client.expire(request["req_id"], 30)
+            except Exception:
+                raise
 
     def callback(self, request):
         """
diff --git a/transfer_service/store_preprocessor.py b/transfer_service/store_preprocessor.py
index ad92bf6750da494757eb7fcfc8fcc3edd9d8b40d..9358c29d9827461f03feabd8901aa0e782e3e231 100644
--- a/transfer_service/store_preprocessor.py
+++ b/transfer_service/store_preprocessor.py
@@ -126,12 +126,21 @@ class StorePreprocessor(TaskExecutor):
                     self.md5calc.recursive(destPath)
             # Case 4: /home/user/store is empty (this should be handled by data_rpc_server.py)
             else:
-                self.logger.critical("FATAL: the 'store' directory is empty, the application MUST to be restarted.")
+                self.logger.critical("FATAL: the 'store' directory is empty")
+                time.sleep(5)
+                sys.exit(1)
 
             # Third scan after directory structure 'check & repair'
             self.logger.info("Recursive scan of the 'store' directory")
             [ dirs, files ] = self.systemUtils.scanRecursive(self.path)
-        
+            
+            try:
+                locationId = self.dbConn.getLocationId(self.storageId)
+            except Exception:
+                self.logger.exception("FATAL: unable to obtain the location ID for the storage point")
+                time.sleep(5)
+                sys.exit(1)
+            
             self.logger.info("Checksum calculation and file catalog update")
             pathPrefix = self.storageStorePath.replace("{username}", self.username)
             tstampWrapperDirPattern = re.compile("/[0-9]{4}_[0-9]{2}_[0-9]{2}-[0-9]{2}_[0-9]{2}_[0-9]{2}-vos_wrapper")
@@ -144,8 +153,7 @@ class StorePreprocessor(TaskExecutor):
                         tstampWrapperDir = tstampWrapperDirPattern.search(basePath).group(0).lstrip('/')
                         basePath = tstampWrapperDirPattern.sub("", basePath)
                         cnode.setWrapperDir(tstampWrapperDir)                
-                    cnode.setParentPath(basePath)
-                    locationId = self.dbConn.getLocationId(self.storageId)
+                    cnode.setParentPath(basePath)                    
                     cnode.setLocationId(locationId)
                     cnode.setJobId(self.jobId)
                     cnode.setCreatorId(self.userId)
@@ -154,17 +162,22 @@ class StorePreprocessor(TaskExecutor):
 
                     vospacePath = basePath + '/' + nodeName
 
-                    if os.path.islink(dir):
-                        # node is a symlink, do not import it...
-                        now = dt.now().isoformat()
-                        self.nodeList.append([ now, dir, vospacePath, "container", "SYMLINK" ])
-                    elif self.dbConn.insertNode(cnode):
-                        now = dt.now().isoformat()
-                        self.nodeList.append([ now, dir, vospacePath, "container", "DONE" ])
-                    else:
-                        # node already exists, skip it...
-                        now = dt.now().isoformat()
-                        self.nodeList.append([ now, dir, vospacePath, "container", "SKIPPED" ])
+                    try:
+                        if os.path.islink(dir):
+                            # node is a symlink, do not import it...
+                            now = dt.now().isoformat()
+                            self.nodeList.append([ now, dir, vospacePath, "container", "SYMLINK" ])
+                        elif self.dbConn.insertNode(cnode):
+                            now = dt.now().isoformat()
+                            self.nodeList.append([ now, dir, vospacePath, "container", "DONE" ])
+                        else:
+                            # node already exists, skip it...
+                            now = dt.now().isoformat()
+                            self.nodeList.append([ now, dir, vospacePath, "container", "SKIPPED" ])
+                    except Exception:
+                        self.logger.exception("FATAL: unable to update the file catalog")
+                        time.sleep(5)
+                        sys.exit(1)
 
             for flist in files:
                 for file in flist:
@@ -177,7 +190,6 @@ class StorePreprocessor(TaskExecutor):
                             basePath = tstampWrapperDirPattern.sub("", basePath)
                             dnode.setWrapperDir(tstampWrapperDir)                    
                         dnode.setParentPath(basePath)
-                        locationId = self.dbConn.getLocationId(self.storageId)
                         dnode.setLocationId(locationId)
                         dnode.setJobId(self.jobId)
                         dnode.setCreatorId(self.userId)
@@ -187,39 +199,46 @@ class StorePreprocessor(TaskExecutor):
                     
                         vospacePath = basePath + '/' + nodeName
 
-                        if os.path.islink(file):
-                            # node is a symlink, do not import it...
-                            now = dt.now().isoformat()
-                            self.nodeList.append([ now, file, vospacePath, "data", "SYMLINK" ])
-                        elif self.dbConn.insertNode(dnode):
-                            now = dt.now().isoformat()
-                            self.nodeList.append([ now, file, vospacePath, "data", "DONE" ])
-                        else:
-                            # node already exists, skip it...
-                            now = dt.now().isoformat()
-                            self.nodeList.append([ now, file, vospacePath, "data", "SKIPPED" ])
+                        try:
+                            if os.path.islink(file):
+                                # node is a symlink, do not import it...
+                                now = dt.now().isoformat()
+                                self.nodeList.append([ now, file, vospacePath, "data", "SYMLINK" ])
+                            elif self.dbConn.insertNode(dnode):
+                                now = dt.now().isoformat()
+                                self.nodeList.append([ now, file, vospacePath, "data", "DONE" ])
+                            else:
+                                # node already exists, skip it...
+                                now = dt.now().isoformat()
+                                self.nodeList.append([ now, file, vospacePath, "data", "SKIPPED" ])
+                        except Exception:
+                            self.logger.exception("FATAL: unable to update the file catalog")
+                            time.sleep(5)
+                            sys.exit(1)
             self.logger.info("Overall data size calculation")
             self.jobObj.jobInfo["dataSize"] = self.systemUtils.getSize(self.path)
             self.logger.info("========== End of preprocessing phase ==========")
         except Exception:
-            self.logger.exception("FATAL: something went wrong during the preprocessing phase.")
+            self.logger.exception("FATAL: something went wrong during the preprocessing phase")
+            self.update("ERROR")
             time.sleep(5)
             sys.exit(1)
         
-    def update(self):
-        self.logger.info("Job phase updated to QUEUED")
-        self.jobObj.setPhase("QUEUED")
-        self.dbConn.setPhase(self.jobId, "QUEUED")
-        
-        # Send e-mail notification
-        m = Mailer(self.logger)
+    def update(self, status):
+        try:
+            m = Mailer(self.logger)
                 
-        m.addRecipient(self.adminEmail)
-        userEmail = self.dbConn.getUserEmail(self.jobObj.ownerId)
-        if userEmail != self.adminEmail:
-            m.addRecipient(userEmail)
-        
-        msg = f"""
+            m.addRecipient(self.adminEmail)
+            userEmail = self.dbConn.getUserEmail(self.jobObj.ownerId)
+            if userEmail != self.adminEmail:
+                m.addRecipient(userEmail)
+            
+            if status == "OK":
+                self.logger.info("Job phase updated to QUEUED")
+                self.jobObj.setPhase("QUEUED")
+                self.dbConn.setPhase(self.jobId, "QUEUED")
+                # Send e-mail notification
+                msg = f"""
         Dear user,
         your job has been QUEUED.
 
@@ -232,8 +251,37 @@ class StorePreprocessor(TaskExecutor):
         You will be notified by email once the job is completed.
 
         """
-        m.setMessage("VOSpace data storage notification: Job QUEUED", msg)
-        m.send()
+                m.setMessage("VOSpace data storage notification: Job QUEUED", msg)
+                m.send()
+            else:                
+                # Send e-mail notification
+                self.logger.info("Job phase updated to ERROR")
+                self.jobObj.setPhase("ERROR")
+                self.jobObj.setErrorType("fatal")
+                self.dbConn.insertJob(self.jobObj)
+                self.dbConn.setEndTime(self.jobId)
+                self.setDestinationQueueName("write_terminated")
+                
+                msg = f"""
+        Dear user,
+        your job FAILED during the preprocessing phase.
+
+        Job ID: {self.jobId}
+        Job type: {self.jobObj.type}
+        Storage type: {self.storageType}
+        Storage ID: {self.storageId}
+        Owner ID: {self.jobObj.ownerId}
+
+        The issue will be automatically reported to the administrator.
+
+        """
+                m.setMessage("VOSpace data storage notification: Job ERROR", msg)
+                m.send()
+        except Exception:
+            self.logger.exception(f"Unable to update the job status for job {self.jobId}")
+        finally:
+            self.jobObj.jobInfo["nodeList"] = self.nodeList.copy()
+            self.nodeList.clear()
 
     def run(self):
         self.logger.info("Starting store preprocessor...")
@@ -249,13 +297,15 @@ class StorePreprocessor(TaskExecutor):
                 self.userId = self.jobObj.ownerId
                 self.username = self.jobObj.jobInfo["userName"]
                 self.prepare(self.username)
-                self.execute()
-                self.jobObj.jobInfo["nodeList"] = self.nodeList.copy()
-                self.nodeList.clear()
-                self.update()
-                self.destQueue.insertJob(self.jobObj)
-                self.srcQueue.extractJob()                
-                self.logger.info(f"Job {self.jobObj.jobId} MOVED from {self.srcQueue.name()} to {self.destQueue.name()}")
+                self.execute()                
+                self.update("OK")
+                try:
+                    self.destQueue.insertJob(self.jobObj)
+                except Exception:
+                    self.logger.exception(f"Failed to move job {self.jobObj.jobId} from {self.srcQueue.name()} to {self.destQueue.name()}")
+                else:
+                    self.srcQueue.extractJob()                
+                    self.logger.info(f"Job {self.jobObj.jobId} MOVED from {self.srcQueue.name()} to {self.destQueue.name()}")
 
 # Test
 #sp = StorePreprocessor()