Zimbra is not forwarding email
I have several domains which is serviced by Zimbra. My colleague have informed me that email forwarding is not working and I have checked and found the following:
1. User A can send email to User B and vice versa.
2. User A configured his zimbra account to forward a copy of the email to User B who are from different domains.
3. Using an external email account (eg. gmail), email sent to User A are received but User B did not received any forwarded email from User A.
4. Reverse the above and the same things happens.
5. Now User A configured his zimbra account to forward a copy of the email to his external email account (eg. gmail).
6. User A sent an email from his Yahoo account to his office account, same thing, the email get received in User A's office account but a copy was not forwarded to his gmail account.
I have tried checking the zimbra logs and cannot seem to find where the problem lies. Could any of you tell me where to look to isolate the issue?
Thanks & Regards.