Hi. How do I uninstall an XP repair process that cannot be completed because I am misplaced the correct activation key to complete the process?

My laptop had been rather slow for a couple of weeks so I proceeded to defrag my hard drive when it suddenly took me to an error message indicating that the file "nostrolkrnl.exe" file was either corrupt or missing. I then replaced the file using the recovery console on an XP installation disk. This however took me to a "blue screen of death" (BSOD) message reading: "STOP: COOOO21a {fatal system error 0x00000000 0x00000000}. The session manager initiation system process terminated unexpectedly with a status of 0xc000026c".

At this point, I proceeded to fix my Windows by using the repair function in my XP Professional installation disk. However I was unable to complete the process as I lost the key (I didn’t think it would ask me for the key if only using the repair function). Please note that the installation disk I used to repair my window is not the original one for my laptop. I bought the laptop "used" with no accompanying disks. The laptop now is in a state where it only prompts me for the activation key (after the Windows splash screen) and does not offer me the option to uninstall this repair.

Please let me know if it is possible to uninstall this and/or (assuming it’s possible) how to repair the BSOD. The BSOD message doesn’t show now, but I figure it will if as soon as I am able to uninstall the repair.

Also note that my hard drive appears to be fine as it passed several tests using Techies Toolkit software.