A fresh install of ZIMBRA OS on Deb5,
Emails with some text lines goes through, from Thunderbird client and also through Zimbra UI, but when i try to send it with an attachment, it fails to send through Thunderbird.
The error message says, SMTP failed to send message through xxxx server, request timed out. Please contact network administrator.
Its not with the firewall for sure as i can send text emails. When i tried sending attached files from UI, it doesn't even go through the attachment window.
Does anyone have a clue why it is doing like that.