mshost.exe is a Trojan W32.Rbot-AND. mshost.exe opens a back door. mshost.exe monitors user Internet activity and private information. It sends stolen data to a hacker site. Related files: %System%\mshost.exe More info: http://www.sophos.com/virusinfo/analyses... Removal: Kill mshost.exe process and remove mshost.exe from Windows startup using antivirus (also check How To Remove section)Startup Optimizer.