1) run PC from Win XP instalation disk
2) on 1st screen of installation process choice ‘R’ and then choise path (default 1), confirm and type yr admin password
3) go to Win XP instalation disk (default e: drive) and then go to e:\i386\ dir
4) copy and replace files csrss.exe, win32k.sys, winlogon.exe and msgina.dll in c:\windows\system32 by these once in e:\i386\ dir (just remember that files in e:\i386\ dir have diff extensions, so to copy use comand eg. (when yr current dir is e:\i386\) copy msgina.dl_ c:\windows\system32\msgina.dll)
5) after that its done, you can restart PC and scan it on virussen