DHelp.dll is worm W32.Qdens.A. DHelp.dll spreads through QQ Messenger. DHelp.dll tries to terminate antiviral programs installed on a user computer. DHelp.dll downloads a copy of Backdoor.Powerspider. Related files: %Windir%\DHelp.dll %System%\DHelp.dll %System%\wmimgr.exe %System%\wbem\DHelp.dll Adds the value: "Windows Management Instrumentation" = "%System%\wmimgr.exe" to the Windows startup registry keys. More info: http://securityresponse.symantec.com/avc... Removal: Remove DHelp.dll from Windows startup using antivirus (also check How To Remove section)Startup Optimizer.