error message after boot screen

I keep getting this error message "STOP C000021a. Fatal System Error The
session manager initialization system process terminated unexpectedly with a
status of 0xc0000263 (0x00000000 0x00000000)." right after the boot screen
and just before login screen. Message appears for 5 secs then laptop reboots
again and does it all over again. cant get to the login screen. I am running
xp home on gateway 450x laptop. called tech supp. and they have no idea what
could be wrong. they want me to send it in but I don't think so. problem
started when I went into safe mode , logged on as admin ,then off,then
logged onto my personal account and off (while in safe mode the whole time),
then I rebooted into normal start. just get login screen the message, login
screen then mess. ANY help would be appreciated.could not even get to login
screen to wipe HD clean.

Thanks
Rob

 

It sounds like the system no longer has permission to access system files and folders. It could also be a problem with winlogon.exe or the Client Server Runtime Subsystem (CSRSS). If security is compromized, the computer will stop.

Did you modify any account or folder permissions while in Safe Mode?

 

You might try reinstalling over the top. Ntoskrnl.exe may be corrupt.
Install as usual, and after the screen where you accept the license agreement, just press "R" to repair your installation.