I am currently facing a major issue with spam emails. My server/ users are sending out a great no of spam emails to other companies. This is causing a major issue as our domain is getting blocked by important clients.
I have done a through scan on all the computers and servers and found few Adwares on few computers. I am using sophos anti virus and dns exit to relay my smtp. Over the weekend this particular user sent out 750 emails and exceeded my relay limit. I went over the weekend to see what was going and found out that user's PC was shut down. Does this mean the Exchange is infected?
Please shed some light on this matter as I am running out of options.