W XP doesn't boot - Bad Image AcGenral.DLL

Hi

Windows XP does not boot.
Not even in safe mode.
the problems are:
Isass.exe - The application or DLL C:\Windows\apppatch\AcGenral.DLL is not a valid Windows image.
and then
userinit.exe - The application or DLL C:\Windows\apppatch\AcGenral.DLL is not a valid Windows image.
and
Explorer.exe The application or DLL C:\Windows\system32\iertutil.DLL

Help please!
Thank you very much