Yes, SharePoint workflows are case sensitive!

Recently ran into a BIG issue that caused thousands of emails to be sent, because of this question.

I needed to relink a few hundred InfoPath forms, the library had an associated workflow… So, I opened SharePoint Designer, added a new step to the workflow, and published my changes.

workflow step:
Condition: If Modified By equals domain\Ihayse
Action: Stop the workflow

Why do this?
When you relink the forms in a library, the worklow will be fired.

After receiving emails and IM’s from some happy campers, I knew my workflow was wrong.

My workflow step should have read:
Condition: If Modified By equals domain\ihayse
Action: Stop the workflow

My domain name is my first initial then my last name, all in lowercase.