Display name in sent e-mail from-address uses department name instead of SMTP "friendly name" setting.
How did you even get the emails to work? I've enter an smtp server under the general email settings and also under each department, and the test successfully connected... but when someone submits a ticket, they never get the auto-response and if I reply to a ticket through the admin, the reply never gets emailed to the customer... and I can't find any documentation to troubleshoot the email setup. What else do I need to do?!
The best place to start is the SMTP logs, which are in the App_Data\Logs folder. Most common causes of not emailing out are:
1 - Port 25 blocked by firewall or by your ISP
2- The App_Data\Spool folder has incorrect permissions