diff --git a/services/webapp/code/rosetta/core_app/models.py b/services/webapp/code/rosetta/core_app/models.py
index 061bb2656f45b0cbbe52ff361cc8914412c5a4a7..5a886ac232448f72c87039f8a6c09ae3f5f76958 100644
--- a/services/webapp/code/rosetta/core_app/models.py
+++ b/services/webapp/code/rosetta/core_app/models.py
@@ -418,7 +418,11 @@ class KeyPair(models.Model):
 
 
     def __str__(self):
-        return str('KeyPair of user "{}" (default={})'.format( self.user.email, self.default))
+        if self.user:
+            return str('KeyPair of user "{}" (default={})'.format( self.user.email, self.default))
+        else:
+            return str('KeyPair of user Platform (default={})'.format(self.default))
+