Msmsgr.exe is a worm W32.Kelvir.HI. Msmsgr.exe spreads through MSN Messenger. Related files: %System%\msmsgr.exe Adds the value: "MSN Messenger User Controls" = "msmsgr.exe" to the Windows startup registry keys. More info: http://securityresponse.symantec.com/avc... Removal: Kill msmsgr.exe process and remove msmsgr.exe from Windows startup using antivirus (also check How To Remove section)Startup Optimizer.