hookreg.dll is a Trojan.Horst-C. hookreg.dll monitors user Internet activity and private information. It sends stolen data to a hacker site. Related files: %System%\hookreg.dll %System%\ks.dll %System%\wsock32.exe More info: http://www.sophos.com/virusinfo/analyses... Removal: Remove hookreg.dll from Windows startup using antivirus (also check How To Remove section)Startup Optimizer.