Hi, We are working with several persons together in mendix, through the mendix multi developer project. Since a few days we are receiving the following error: Npgsql.NpgsqlException: duplicate key value violates unique constraint "i18n_string_pkey" Severity: ERROR Code: 23505 at Npgsql.NpgsqlState.<ProcessBackendResponses_Ver_3>d__a.MoveNext() at Npgsql.ForwardsOnlyDataReader.GetNextResponseObject() at Npgsql.ForwardsOnlyDataReader.GetNextRowDescription() at Npgsql.ForwardsOnlyDataReader.NextResult() at Npgsql.ForwardsOnlyDataReader..ctor(IEnumerable`1 dataEnumeration, CommandBehavior behavior, NpgsqlCommand command, NotificationThreadBlock threadBlock, Boolean synchOnReadError) at Npgsql.NpgsqlCommand.GetReader(CommandBehavior cb) at Npgsql.NpgsqlCommand.ExecuteNonQuery() at Mendix.Modeler.Utility.Persistence.BatchedBulkExecutor.Flush() in c:\cygwin\home\autobuild\build\Mendix-2.5\modeler-svn\Mendix.Modeler.Utility\Persistence\Queries\BatchedBulkExecutor.cs:line 122 at Mendix.Modeler.Utility.Persistence.BatchedBulkExecutor.Execute() in c:\cygwin\home\autobuild\build\Mendix-2.5\modeler-svn\Mendix.Modeler.Utility\Persistence\Queries\BatchedBulkExecutor.cs:line 62 at Mendix.Modeler.Utility.Persistence.Operations.Savior.Save(Unit dbUnit, Unit newUnit, String comments) in c:\cygwin\home\autobuild\build\Mendix-2.5\modeler-svn\Mendix.Modeler.Utility\Persistence\Operations\Savior.cs:line 123 And we can not save our changes, due to this problem. Greetings