Fix: Cannot Telnet from computer running McAfee VirusScan due to port blocking rules

I’ve been trying to troubleshoot an email server problem all day, and one of the tests I’ve been performing is trying to connect to port 25 of the mail server through Telnet.  Every time I tried I get connection refused messages, and the connection would drop. 

My work computer is running McAfee VirusScan Enterprise 8.5.0i and Windows XP SP2.  I verified the Windows XP firewall was disabled and not blocking my connection.
Next I looked at the McAfee VirusScan log file by clicking Start -> Programs -> McAfee -> VirusScan Console.  From the menu I selected Task -> View Log
I quickly noticed the following message:
Blocked by port blocking rule C:\WINDOWS\system32\telnet.exe Anti-virus Standard Protection:Prevent mass mailing worms from sending mail
Obviously McAfee was blocking my attempt to Telnet.  In order to unblock Telnet I did the following:
  1. Started McAfee VirusScan Console
  2. Double clicked Access Protection
  3. Highlighted the Anti-Virus Standard Protection category from the left column
  4. Highlighted the Prevent mass mailing worms from sending mail rule in the right column

  6. Pressed Edit
  7. Under Processes to Exclude, I put my cursor at the end of the list of processes, which was winpm-32.exe in my case.  I typed a comma following winpm-32, exe, and then added a space and telnet.exe to the list
  8.  I pressed OK twice, exited VirusScan Console, and was able to Telnet to my mail server.
For more information, see McAfee KB42354

Comments [2]

  1. Even after I do all the above steps you mentioned, I could not telnet to my mailserver on port 25, any guidance is greatly appreciated.

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