HELP: c000021a unknown hard error

[bjude]

I am using Windows XP SP2 here. There were some recent updates installed on my system last night and after that I started facing problem with login. The pc cannot boot up properly. When I enter my user id and password after a few seconds there is a blue screen. The error message which was listed on the screen is "C000021A unknown hard error". I am using Windows XP CD to fix the issue but nothing works here. How can I remove the updates that are installed. I think by removing the update the problem will be fixed.

[Illeana]

Try to boot in safe mode and then try back. At the time of restart press F8 continuously. And choose safe mode with command prompt. In that type the following command chkdsk /r. If this does not work then go back in command prompt and simply go in control panel > windows component. Remove the updates and the last thing you can do is run a repair setup of Windows XP. This setup does not make any changes in your system but replaces the system files.