i have a samsung dc10 netbook, and when i turn it on i get the above error, nothing i do will work, i cant start up in safe mode it just goes back to c000021a. and as its a net book i cant reinstall OS as i have no drive,

someone please heeeeeeeeelllllllllllppppppppppp...

Usually, Last Know Good Configuration will resolve the problem; if not, tell us more about the problem. Please give careful though to the following, as it will determine the next step int he troubleshooting process:

Are you using, or have you installed any remote control software?
Do you login to a workgroup, or domain environment?
Does your computer use biometric, or other third-party login software?
Were any device drivers altered just before the problem occurred?

I suspect a corrupt, missing,or replaced Graphical Identification and Authentication (GINA) DLL. GINA is a component that Winlogon.exe loads. If it is no found, it tries to find the backup. If the backup can't be found, the error is generated. This may require an XP CD.