Rebuild the boot.ini.
Boot the computer with recovery console or with os cd and go to recovery
console
The bootcfg /rebuild command scans the hard disks of the computer for
Windows NT 4.0, Windows 2000, or Windows XP installations, and then displays
the results. You can add the detected Windows installations.
You may receive a message that is similar to the following message:
Total Identified Windows Installs: 2
[1] C:\Windows
Add installation to boot list? (Yes/No/All):
Enter Load Identifier: (Custom description for an operating system loading
from the Boot menu)
Enter Operating System Load Options: (that is: /fastdetect)
[2] D:\Windows
Add installation to boot list? (Yes/No/All):
Enter Load Identifier: (Custom description for an operating system loading
from the Boot menu)
Enter Operating System Load Options: (that is: /fastdetect)
Uninstall the service pack2
Follow this
How to remove Windows XP Service Pack 2 from your computer
View products that this article applies to.
Important This article contains information about modifying the registry.
Before you modify the registry, make sure to back it up and make sure that
you understand how to restore the registry if a problem occurs. For
information about how to back up, restore, and edit the registry, click the
following article number to view the article in the Microsoft Knowledge Base:
256986 Description of the Microsoft Windows Registry
SUMMARY
This article describes how to remove Microsoft Windows XP Service Pack 2
(SP2) from your computer.
MORE INFORMATION
Note You cannot remove Windows XP SP2 if you installed the service pack on a
computer that already had Windows XP SP2 installed. The removal program will
roll back to the version of Windows that existed before your installation. In
this case, the program will roll back to the first installation of Windows XP
SP2.
Use any one of the following methods to remove Microsoft Windows XP SP2 from
your computer:
Use the Add or Remove Programs tool in Control Panel
Use the hidden $NtServicePackUninstall$ folder
Use the System Restore process
Use Recovery Console
Important We recommend that you use the following methods in the order that
they are listed.
Use the Add or Remove Programs tool in Control Panel
Click Start, click Run, type appwiz.cpl in the Open box, and then click OK.
Click to select the Show Updates check box.
Click Windows XP Service Pack 2, and then click Remove.
Follow the instructions on the screen to remove Windows XP SP2.
Use the hidden $NtServicePackUninstall$ folder
Click Start, click Run, type
c:\windows\$NtServicePackUninstall$\spuninst\spuninst.exe in the Open box,
and then click OK.
When the Windows XP Service Pack 2 Removal Wizard starts, click Next.
Follow the instructions on the screen to remove Windows XP SP2.
Use the System Restore process
Click Start, click Run, type %SystemRoot%\System32\restore\rstrui.exe in the
Open box, and then click OK.
Click Restore my computer to an earlier time, and then click Next.
Click the date that you installed Windows XP SP2, and then click Installed
Window XP Service Pack 2 in the Restore Point box.
Click Next, and then follow the instructions on the screen to remove Windows
XP SP2.
Use Recovery Console
Warning If you use Registry Editor incorrectly, you may cause serious
Repair windows with windows xp installation repair.
Do Clean installation.
