Our SBS 2008 x64 Server with Exchange 2007 IP is constantly being blocked as a spammer or part of a BotNet over the past 8 days. We can find no offending machines and most of our client machines connect using VPN. We are well protected with corporate McAffe software that also blocks smtp port 25 mass mailing worms and a Cisco 891W-AGN-A-K9 Router. I have run speial diagnostics with the help of MCafee to be certain servers are clean.
All service Packs and updates installed.
We can receive emails but cannot send.
I have turned off wireless networking in all offices, I am stumped.
We have the SBS Server, a separate Terminal Services Server and a VMware VM machine runningBlackBerry EnterpriseServer Express under the Terminal Server. Could the BB Phones email cause this problem? I have them shut down for 48 hrs.
Is there any wisdom to changing our SMTP port? What is the MS Best Practices scenario for Port 25/Exchange/Spam/BotNet?
If yes how would that be accomplished in the SBS environment that uses Outlook and Outlook OWA on client machines? I have basic knowledge only.
Thank you!
joe....
Thanks!