diff --git a/src/cluster/cluster.cpp b/src/cluster/cluster.cpp
index baef86e4412c43ef677d15edc043ad56021bef0a..ba832a4f0dbe8f141d215eb6b6049f3ee719971c 100644
--- a/src/cluster/cluster.cpp
+++ b/src/cluster/cluster.cpp
@@ -326,6 +326,9 @@ void cluster(const string& config_file, const string& data_file, const string& o
 	return;
       }
 
+      //==================================================
+      // do the first outputs here, so that I open here the new files, afterwards I only append
+      //==================================================
       vtppoanp->write_to_disk(output_path + "/c_TPPOAN");
       delete vtppoanp;
 
@@ -420,8 +423,8 @@ void cluster(const string& config_file, const string& data_file, const string& o
 	  // the parallel loop over MPI processes covers a different set of indices for each thread
 #pragma omp barrier
 	  int myjxi488 = ixi488+myompthread;
-	  vtppoanp_2 = new VirtualBinaryFile();
 	  // each thread opens new virtual files and stores their pointers in the shared array
+	  vtppoanp_2 = new VirtualBinaryFile();
 	  // each thread puts a copy of the pointers to its virtual files in the shared arrays
 	  vtppoanarray[myompthread] = vtppoanp_2;
 #pragma omp barrier
@@ -521,8 +524,8 @@ void cluster(const string& config_file, const string& data_file, const string& o
 
     else { // NSPH mismatch between geometry and scatterer configurations.
       throw UnrecognizedConfigurationException(
-					       "Inconsistent geometry and scatterer configurations."
-					       );
+	"Inconsistent geometry and scatterer configurations."
+      );
     }
       
     delete sconf;