Infos:
- Used Zammad version: 5.2.3
- Used Zammad installation type: Package
- Operating system: Ubuntu 20.04
- Browser + version: Firefox 105.0
Expected behavior:
- Email Notifications being sent/received.
Actual behavior:
- Email notification being sent internally being blocked.
Issue Explained:
We had Zammad sending notifications fine using Local MTA.
We change to Pfsense Router and notification emails stopped working (Stopped being received).
I changed router to BT and Untangled routers and email notifications worked. Then changed back to Pfsense, and it stopped working again.
So this made me think Pfsense router is blocking the notifications being sent out.
Sending/Receiving emails on Zammad work fine on all routers and not really related to this issue.
My guess is I am going to have to create a firewall (Maybe a port) rule to allow internal Zammad server to send out of the router.
If anyone has any information on what I need to allow on the Firewall, that would be much appreciated.
This is not an issue with Zammad or Pfsense it is just an implementation issue on user (my) end.
Why I created Topic:
I noticed this issue but since we all check Zammad all the time it did not really matter.
I have not spent a good amount of time on reviewing it but thought I would ask if someone seen this issue before,
If not don’t worry, hopefully I can solve the problem.
I will update this ticket once solved. So when someone searches this issue, they will hopefully find a solution.
Thanks:
Thank you for taking the time to read this topic. 
