+ 0 Votes A couple of random thoughts... gechurch April 2, 2013 at 6:29pm PST I had problems when setting up an approval workflow in 2010. It was a custom workflow, and the main problem was the workflow ran under the context of the user who submitted the item. Problem is the 'mark as approved' step. Because it was running under the context of the user that submitted the item, the workflow didn't have permission to change the approval status so it threw an error. The symptoms were quite different for me but nevertheless it's something to check. The fix was to make all the steps use impersonation (in SharePoint Designer). Another possibility (and I can't remember if this is the case or not) but perhaps having the workflow trigger on both upload and change could cause new items to trigger the workflow twice. Perhaps that's causing issue.Those are just two stabs in the dark. To diagnose it properly open up a workflow item (from memory you do this by clicking on 'Pending' or 'Complete' in the workflow status column) and look at it's history/log. If you're making a custom workflow in Designer you can add in log steps - the output of which will show under the history for each workflow.