Hi, I have been trying to use workflow_execute.pl to execute a workflow that has ~50 steps. I keep getting this error after running for few seconds knowing I could run the same workflow from the GUI without any issue. **************** HTTP Error 500: Internal Server Error 500 Internal Server Error The server has either erred or is incapable of performing the requested operation. ********************* And here is some error I capture in the log file> File "/usr/local/galaxy/galaxy-dist/lib/galaxy/tools/__init__.py", line 2126, in execute return self.tool_action.execute( self, trans, incoming=incoming, set_output_hid=set_output_hid, history=history, **kwargs ) File "/usr/local/galaxy/galaxy-dist/lib/galaxy/tools/actions/__init__.py", line 362, in execute history.add_dataset( data, set_hid = set_output_hid ) File "/usr/local/galaxy/galaxy-dist/lib/galaxy/web/framework/__init__.py", line 1124, in __getattr__ if key not in self: raise AttributeError, key AttributeError: add_dataset Looking at the created history the first 14 steps get scheduled and executed. But nothing else. Meaning the rest of the steps get omitted. This could be due to the script get crashed before it complete registering the rest of the steps of the workflow. Does anyone has any idea what could be going on here? Best regards.