Yesterday I tried committing some changes to one of the websites I am maintaining into my CVS repository. To my surprise the operation failed or to be more exact, the TortoiseCVS client just kept performing the command for several minutes without failing until I cancelled it.

After some investigation I realized that it’s been almost two weeks since my last CVS usage and that in the meantime the only noticeable change on my server machine where I have the CVSNT service running was the change of the antivirus software. I started trying out NOD32. It became the primary suspect for the problem.

To make my further investigation easier I decided to try if the CVS works when used locally from the server:

cvs -d :pserver:damir@localhost:/Root login
Logging in to :pserver:damir@localhost:2401:/Root
CVS Password: ******
cvs [login aborted]: Error reading from server localhost: -1

Obviously it didn’t work even locally so it wasn’t a simple problem of firewall blocking the port (although this would be strange without having any firewall enabled at all). Some googling quickly uncovered the program responsible: NOD32 IMON service. Disabling it and restarting the server solved the problem.

But I wasn’t satisfied with that. I didn’t want to disable the internet monitor completely to make the CVSNT work. This would mean that I’d have to go on looking for another antivirus solution while I was completely satisfied with this one up till now. After some more investigation I found a hint that brought me to my final solution: re-enabling the IMON service and excluding the CVSNT executable from the monitoring. The exclusions list can be reached by opening up the NOD32 Control Center under Resident modules and filters > IMON. Setup button in the following window opens up another window with Miscellaneous tab, inside the Exclusion group there's an Edit... button which displays the list. The file that has to be added is cvsservice.exe from the C:\Program Files\CVSNT directory in the case of default installation.