Orders not being sent to supplier via email using ASCP workbench

I have a user that when they release an order though ASCP workbench to certain customers they do not receive the email.  I have verified the supplier's email is valid and setup.  I tested releasing the same part to the same customer with a different user everything worked fine.  Could there be a setting on the users profile that could cause this behavior?   I compared this user with another, but i was not able to see any differences.  If the user creates a release using standard Oracle everything works fine.   Has anyone else seen behavior like this before.  

Thanks

Kenny