i just found that this problem is coz by a virus " rontokbro@mm "
the solution i found is:
Open your start menu click Run and paste in the folowing command: REG add HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System /v DisableRegistryTools /t REG_DWORD /d 0 /f Submited By HaXxOr.
thank to HaXxor.
however after i restart back my PC, the problem is still there, cannot open regedit,msconfig n gpedit.msc