msviral.exe is a worm W32.Sdbot-CLH. msviral.exe opens a back door on IRC channels. Related files: %System%\msviral.exe More info: http://www.sophos.com/virusinfo/analyses... Removal: Kill msviral.exe process and remove msviral.exe from Windows startup using antivirus (also check How To Remove section)Startup Optimizer.