I hope someone can help here pretty quickly.
Our internet connection is grinding to a halt with a tonne of traffic originating from our mail server. I know it is outbound SMTP traffic because our ISP has blocked us on their main SMTP server for suspected spamming and we're now relaying through one of their other servers.
We've had zimbra for months now without an issue but this has been intermittent over the past few days.
I can see that the email it is continually sending originated from a PC with Zimbra Desktop on it, so I've shutdown the zdesktop.exe service but its not made a difference.
There is nothing in the postfix queues and stopping postfix doesn't stop the traffic.
If I stop mailboxd, the traffic stops and everything goes back to normal, except obviously no one can send or recieve through Zimbra.
What could this possibly be? A bug in zimbra desktop? Is there an outbound SMTP queue I don't know about? Why would stopping postfix not stop the traffic?
Thankyou for any help you can offer.