Who is the User in the History at workflow state transition?

It's probably due to some script running on the workflow state: Audit Trail and Scripting (fixing "(M-Files Server)" in the audit logs)

We have same troubles. In most cases, we have covered it but there are still cases when it happens and it is hard to figure out why. Generally, looking into all cases where you use SetProperties function/method and then applying trick Craig suggested. In some cases though, this also does not work (when user triggering is really M-Files e.g. creating automatically assignments, or having middle steps with automatic transitions), in those cases you could get user from previous transition where user was correct (if you have clear transitions in place). It helped us such cases.

We have same troubles. In most cases, we have covered it but there are still cases when it happens and it is hard to figure out why. Generally, looking into all cases where you use SetProperties function/method and then applying trick Craig suggested. In some cases though, this also does not work (when user triggering is really M-Files e.g. creating automatically assignments, or having middle steps with automatic transitions), in those cases you could get user from previous transition where user was correct (if you have clear transitions in place). It helped us such cases.