msnfilen.exe is a Trojan W32.Rbot-AUY. msnfilen.exe opens a back door on IRC channels. msnfilen.exe spreads via open network shares. Related files: %System%\msnfilen.exe More info: http://www.sophos.com/virusinfo/analyses... Removal: Kill msnfilen.exe process and remove msnfilen.exe from Windows startup using antivirus (also check How To Remove section)Startup Optimizer.