I had a Virus in my computer ...i build a ultimate Boot Cd and scanned from it ..it deleted the virus and infected files ..now i cant log on to windows ..it gives me an error
C000021a Status 0xc0000034...i checked microsoft knowledge base for it ..they are telling to run DR watson Debuger ..but the commands tehy say wont work can any one help

1: Can you boot in safe mode? If yes, run Last Known Configuration. If not successful:

2: System Restore from the Recovery Console. {adapted from G2G. Original source unknown to me}. Xp installation CD required. Boot with the CD and when given the option choose to repair the computer by pressing "R", opening the Recovery Console. Type 1 when asked for OS installation (assuming there is only one OS installed. Type the administrator password when asked to do so and press Enter. Press Enter if there is no password.

* At the prompt Type: CD \
* Press Enter
* Type: cd system~1\_resto~1
* Press Enter
* Type: dir
* Press Enter

After you press enter you will see a list of folders (like rp1, rp2) If the list of restore points has more than one page then press the Enter key untill you reach the end of the list

* Type: cd rp {number of the second to last folder in the list). Example: cd rp9, if rp9 is the second to the last restore point where the last restore point no. is 10
* Press Enter
* Type: cd snapshot
* Press Enter
* Type: copy _registry_machine_system c:\windows\system32\config\system
* Press Enter
* Type: copy _registry_machine_software c:\windows\system32\config\software
* Press Enter
* Type: Exit
* Press Enter

Your PC will reboot.

If you get an access denied error when doing the above, then do the following at the recovery console:

* Type: CD \
* Press Enter
* Type: cd windows\system32\config
* Press Enter
* Type: ren system system.bak
* Press Enter
* Type: Exit
* Press Enter

Your PC should reboot

If you still cannot get access in anyway to your installation in the recovery console then your SAM database files are corrupt. There is no way you can restore these with the recovery console. You may need to do a fresh install.

3: If still not successful perform a repair installation for XP. You may use the link in my signature to a guide that will tell you how to perform the repair.

4: If, and after, you boot the computer, move to the malware forum in G2G. Use the link in my signature. It's important that a good helper who knows how to clean malware will check your system.

I Have tried the method listed above still it gives me same Error ....I have XP proff CD with me but my laptop had Xp home and i have lost the CD..is there still any way i recover windows

Have you tried Windows Repair? For this you must have XP Home Edition of the same version that was originally installed. You may borrow one and use the product key of your present installation.

Thanks

Things were looking grim. I formatted and installed XP again