GPinstall.exe is an adware program Adware.PopAdStop. GPinstall.exe monitors user Internet activity. Related files: %Windir%\GPinstall.exe %Windir%\popadstop.exe Adds the value: "PopAdStop"="\popadstop.exe s" to the Windows startup registry keys. More info: http://securityresponse.symantec.com/avc... Removal: Kill GPinstall.exe process and remove GPinstall.exe from Windows startup using antivirus (also check How To Remove section)Startup Optimizer.