System Diagnostic can be removed by stopping and removing all the processes and files with random name in the hard drive and restoring the registry entries added and modified by System Diagnostic. All of them has been shown in the removal guide below.
System Diagnostic should be removed immediately!
System Diagnostic Removal Guide
Kill Process
(How to kill a process effectively?)
[random].exe
Unregister DLL files
%Temp%\[random].dll
Delete Registry
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run "[RANDOM].exe"
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run "[RANDOM]"
HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main "Use FormSuggest" = 'yes'
HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Download "CheckExeSignatures" = 'no'
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Attachments "SaveZoneInformation" = '1'
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Associations "LowRiskFileTypes" = '{hq:/s`s:/ogn:/uyu:/dyd:/c`u:/bnl:/ble:/sdf:/lrh:/iul:/iulm:/fhg:/clq:/kqf:/`wh:/lqf:/lqdf:/lnw:/lq2:/l2t:/v`w:/rbs:'
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\System "DisableTaskMgr" = '1'
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings "WarnonBadCertRecving" = '0'
Remove Folders and Files
%UserProfile%\Start Menu\Programs\System Diagnostic
%UserProfile%\Desktop\System Diagnostic.lnk
%Temp%\[random].dll
%Temp%\dfrgr
%Temp%\dfrg
%Temp%\[random].exe
%AllUsersProfile%\Application Data\[random].exe
%AllUsersProfile%\Application Data\[random].dll
%AllUsersProfile%\Application Data\~[random]
System Diagnostic should be removed immediately!
System Diagnostic Removal Guide
Kill Process
(How to kill a process effectively?)
[random].exe
Unregister DLL files
%Temp%\[random].dll
Delete Registry
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run "[RANDOM].exe"
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Run "[RANDOM]"
HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main "Use FormSuggest" = 'yes'
HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Download "CheckExeSignatures" = 'no'
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Attachments "SaveZoneInformation" = '1'
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Associations "LowRiskFileTypes" = '{hq:/s`s:/ogn:/uyu:/dyd:/c`u:/bnl:/ble:/sdf:/lrh:/iul:/iulm:/fhg:/clq:/kqf:/`wh:/lqf:/lqdf:/lnw:/lq2:/l2t:/v`w:/rbs:'
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\System "DisableTaskMgr" = '1'
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Internet Settings "WarnonBadCertRecving" = '0'
Remove Folders and Files
%UserProfile%\Start Menu\Programs\System Diagnostic
%UserProfile%\Desktop\System Diagnostic.lnk
%Temp%\[random].dll
%Temp%\dfrgr
%Temp%\dfrg
%Temp%\[random].exe
%AllUsersProfile%\Application Data\[random].exe
%AllUsersProfile%\Application Data\[random].dll
%AllUsersProfile%\Application Data\~[random]