Endless Reboot Loop While “Configuring Updates: Stage 3 of 3” During Vista SP1 Installation

In the middle of the process to install Windows Vista SP1, when the on-screen status message showing “Configuring updates: Stage 3 of 3 – 0% complete”, the system will suddenly going into shutdown and reboot. Worse still, after computer starts up again, it will comes to the same configuration screen, and goes into reboot again. The computer restarts error repeated itself again and again, causing endless reboot loop. The symptom also happens when boot into Safe Mode. Of course, the service pack update is not installed successfully.

This problem occurs when Windows Update is installing update 937287 for Windows Vista, according to Microsoft KB949358, which should has been fixed with publishing of KB949939. If you’re still encountering the problem, try the following steps to get your system working again.

Method 1: Start Windows Vista by using the Windows installation media, and then select the “Repair your computer” option

Note: If the computer came with Windows Vista preinstalled, you may not have Windows installation media. If you do not have Windows installation media, go to method 2.

1. Insert the Windows Vista installation disc in the DVD drive, and then restart the computer.
2. Press any key when you are prompted to start from the disc.

   Note: If the computer is not configured to start from a CD or from a DVD, you have to change the BIOS settings to set first boot device to CD/DVD drive.

3. When you are prompted, configure the Language to install, Time and currency format, and Keyboard or input method options that you want, and then click Next.
4. On the next page, click Repair your computer.
5. On the System Recovery Options page, click the version of the Windows Vista operating system that you want to repair, and then click Next.
6. On the System Recovery Options page, click System Restore.
7. On the System Restore page, click Next.
8. Select a restore point at which you know that the operating system was working, and then click Next.

   The restore point should be a date that occurred before you experienced the problem that is described in the “Symptoms” section. To select this date, use the Choose a different restore point option, and then click Next.

9. If you are prompted for a disk to restore, select the disk to which the operating system is installed, and then click Next.
10. On the Confirm your restore point page, click Finish.
11. When the restoration process is complete, click Restart.

Method 2: Start the computer in safe mode, and then use the Repair or System Restore feature

1. Make sure that there are no floppy disks, CDs, or DVDs in the computer, and then start the computer.
2. Use one of the following procedures, as appropriate for your situation:
   • If the computer has a single operating system installed, press and then hold the F8 key as the computer starts. You have to press F8 before the Windows logo appears. If the Windows logo appears, you must try again by turning off the computer and then restarting the computer.
   • If the computer has more than one operating system installed, use the arrow keys to highlight the operating system that you want to start in safe mode, and then press F8.
3. On the Advanced Boot Options screen, use the arrow keys to select the safe mode option that you want, and then press ENTER.
4. Log on to the computer by using a user account that has administrator rights.
5. Click Start, type system restore in the Start Search box, and then click System Restore under the Programs section. Alternatively, type in rstrui.exe.

   When you are prompted by the User Account Control feature, click Continue.

6. On the System Restore page, click Next.
7. Select a restore point at which you know that the operating system was working, and then click Next.

   The restore point should be a date that occurred before you experienced the problem that is described in the “Symptoms” section. To select this date, use the Choose a different restore point option, and then click Next.

8. If you are prompted for a disk to restore, select the disk to which the operating system is installed, and then click Next.
9. On the Confirm your restore point page, click Finish.
10. When the restoration process is complete, click Restart.

Method 3: Rename the Pending.xml file (and optionally CleanUp.xml), and then edit the registry

This method provides a mean for users have tried all other methods but failed to recover, and computer has no restore points or cannot start to a repair option that offers the System Restore feature. However, it’s just a way to recover computer to bootable state, which users should determine if there is still problem with updating process, and decide whether to backup the data and reinstall Windows.

1. Insert the Windows Vista installation disc in the DVD drive, and then restart the computer.
2. Press any key when you are prompted to restart from the disc.
3. When you are prompted, configure the Language to install, Time and currency format, and Keyboard or input method options that you want, and then click Next.
4. On the Install Windows page, click Repair your computer.
5. On the System Recovery Options page, click the version of the Windows Vista operating system that you want to repair, and then click Next.
6. On the System Recovery Options page, click Command Prompt.
7. Type cd C:\windows\winsxs, and then press ENTER.
8. Type ren pending.xml pending.old, and then press ENTER.

   Note: If pending.xml alone doesn’t work to resolve problem, try to rename also cleanup.xml.

9. Type regedit, and then press ENTER.
10. Select HKEY_LOCAL_MACHINE.
11. On the File menu, click Load Hive.
12. Locate the following folder:

    C:\windows\system32\config\components

13. When you are prompted for a name, type Offline_Components.
14. In Registry Editor, locate and then delete the following registry subkey:

    HLKM\Offline Components\AdvancedInstallersNeedResolving

15. In Registry Editor, locate and then delete the following registry subkey:

    HKLM\Offline Components\PendingXmlIdentifier

16. Exit Registry Editor, type exit at the command prompt, and then press ENTER.
17. Click Restart, Windows should boot into the same “Configuring updates” screen, but the screen will disappear in a short while, and system will be able to boot into desktop.

Note: Failure to delete the registry keys in method 3 will cause check user unable to check for latest updates in Windows Update with error code 8000ffff.