XP unbootable after SP2 installation

[Guest]

I installed service pack 2 and everything went well, but when the
installation restarts to complete, windows becomes unbootable. I could not
access the desktop. I can only see the boot screen and immediately after,
BSOD comes. SO far i found three error messages.
1)Stop c000021a {Fatal System Error}
Session Manager Initialization System Process Terminated Unexpectedly
with a
status
of 0xc000026c (0x00000000 0x00000000)
2)Stop : c0000221 Unknown Hard Error
\SystemRoot\System32\ntdll.dll
3)The Unhandled Exception in Session Manager system process terminated
unexpectedly
with a status of 0xc0000005 (0x7c914d34 0x0015fb08)

What gives? How do i solve this problem? The supprot professional i
contacted told me to install SP2 in safemode but the BSOD still comes.
Regards.

 

[Jupiter Jones [MVP]]

Check here for information on the Stop Errors:
http://aumha.org/win5/kbestop.htm

For Reboot issue:
How to use the Automatic Recovery feature to recover your computer if the
Windows XP Service Pack 2 Setup program is not completed successfully:
http://support.microsoft.com/?id=875355

Reboot tapping F8 each second.
Select "Last known good configuration" at the menu.
If that fails, reboot tapping F8 again this time choosing Safe Mode.
Then System Restore to Date/Time before issue started:
Start/All Programs/Accessories/System Tools/System Restore

Otherwise perform a Repair Installation:
http://www3.telus.net/dandemar/repaxp.htm

When you are ready for SP-2, follow the Service Pack Installation Checklist:
http://www3.telus.net/dandemar/spackins.htm