A client called the other day to ask why the FROM address on workflow emails was not working properly.  We took a look at the workflow FROM settings and they looked fine.  Then we took a look at the Outgoing Server settings and found the answer.  The from email, instead of being left blank was filled in with an email address.

In the outgoing server settings, if you fill in an email address on the FROM email, it will over-ride all outgoing emails — whether from workflows or regular vtiger emails — and that will be the FROM email on all emails.  So, bottom line, don’t fill it in.