How to remove service pack 2 or 3 when windows fails to boot...

[AMD]

http://support.microsoft.com/kb/950249

Method 4: Use Recovery Console
Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
322756 (http://support.microsoft.com/kb/322756/ ) How to back up and restore the registry in Windows

If you cannot remove Windows XP SP3 by using one of the previous methods, follow these steps:
Insert the Windows XP CD in the CD drive or in the DVD drive, and then restart your computer. When you receive the following message, press a key to start your computer from the Windows XP CD:
Press any key to boot from CD
Note The computer must be configured to start from the CD drive or from the DVD drive. For more information about how to configure your computer to start from the CD drive or from the DVD drive, see the documentation that was included with your computer, or contact the computer manufacturer. You can also use a bootable floppy disk to start Windows XP. For more information, see the following Microsoft Knowledge Base article:
305595 (http://support.microsoft.com/kb/305595/ ) How to create a bootable floppy disk for an NTFS or FAT partition in Windows XP
When you receive the Welcome to Setup message, press R to start the Recovery Console.

Note Multiple options will appear on the screen.
Select the correct Windows XP installation.

Note You must select a number before you press ENTER, or the computer will restart. Typically, only the 1: C:\Windows selection is available.
If you are prompted to type an administrator password, do so. If you do not know the administrator password, press ENTER. (Typically, the password is blank.)

Note You cannot continue if you do not have the administrator password.
At the command prompt, type cd $ntservicepackuninstall$\spuninst, and then press ENTER.
At the command prompt, type batch spuninst.txt, and then press ENTER.

Note The Spuninstal.txt file appears. As the file scrolls down, you will see errors and the files that are being copied. This is typical behavior.
After Windows XP SP3 is removed, type exit, and then press ENTER.
Restart the computer in safe mode. To do this, press F8 when the computer restarts.

Note After you restart the computer, the computer may stop responding, and you may see a black screen. The mouse will work. In this case, restart the computer again by turning the computer off and then back on. The second restart will let you log on.
When the computer restarts, Windows Explorer (Explorer.exe) does not run, and the Windows icons and the Start button are unavailable. To resolve this problem, follow these steps:
Press CTRL+ALT+DEL, and then click Task Manager in the Windows Security screen.
Click File, and then click New Task (Run).
In the Open box, type regedit, and then click OK.
Locate and then click the following registry subkey:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Servic es\RpcSs
In the details pane, right-click ObjectName, click Modify, type LocalSystem in the Value data box, and then click OK.
Restart the computer
Use one of the previous methods to remove Windows XP SP3 from your computer.
For more information about how to install and use the Recovery Console, click the following article number to view the article in the Microsoft Knowledge Base:
307654 (http://support.microsoft.com/kb/307654/ ) How to install and use the Recovery Console in Windows XP

http://support.microsoft.com/kb/950249

[lycan246]

I have a way that might be easyier, It dosn't remove service packs so much as tricking windows into thinking its a different service pack

Open run and type "regedit"

Then expand HKEY_LOCAL_MACHINE

Then expand CurrentControlSet

Then expand Control

Then scroll down until you find Windows

Click that key to expand it then on the right look for CDSVersion

Then Double click that to open it.

Then in the feild called "Value Data" there will be a number and that number will indecate what service pack you. So if it says "3" then you have SP3, and if it says "2" then you have SP2, and iff it says "0" then you dont have a service pack. The its a simple matter of changing the number to what ever service pack you want it to be (you will need to restart your system before it will reconize the changes).Now if you open system properties or type "winver" into the run command box it will tell you whatever number you put in it will be that service pack. This will not delete SP3 files and will not permantly hurt your system you just have to go back in and tell it what service pack it is, I have found this to be helpful to know at times as it might also ask you to re-avtivate your copy of windows.

This is just another option i mean no disrespect to the author of this thread and i am not trying to start a flame war :P

[linuxguru]

Format

[Deathhawk78]

Format


I was thinking the same thing. Much easier less complications.

Some people do like challenges.

[Mindcore]

I have to agree. I tried to roll back SP3 once by using first Add/Remove Programs and then trying System Restore. My system remained buggered up. It was easier to format and reinstall.

[SPARKY]

I agree also, format and reinstall, and how do know it's the service pack that's causing Windows not to boot, it could be a waste of time, and why would you want to remove a service pack ?

[AMD]

I agree also, format and reinstall, and how do know it's the service pack that's causing Windows not to boot

Failure to boot right after installing a service pack is a good indication. :rolleyes:

[ZAX]

Or it could be an update.