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