Encountered the dreaded “computer restarted unexpectedly or encountered an unexpected error” message on Windows 11? Dive into this guide to understand the issue and explore potential solutions.

Introduction to the Unexpected Restart Error in Windows 11 With the rollout of Windows 11, many users have embraced the new features and enhancements. However, like any software update, it’s not without its hiccups. One such issue is the unexpected Restart Error, which can be both confusing and frustrating.

But don’t worry, you’re not alone. Many users have faced this issue, and there are tried-and-tested solutions available. Let’s dive into the details.

Understanding the Issue

When trying to use a recovery disk or install Windows 11, users may encounter an error message stating, “The Computer restarted unexpectedly or encountered an unexpected error. Windows installation cannot proceed. To install Windows, click “OK” to restart the computer, and then restart the installation.” This issue primarily arises when restoring a Windows machine to factory settings using a recovery disk.

Understanding the Root Causes

1. Incomplete Updates: Sometimes, interrupted or incomplete updates can cause system instability.
2. Driver Conflicts: Incompatible or outdated drivers might not gel well with Windows 11, leading to errors.
3. Software Incompatibility: Some older software versions might not be optimized for Windows 11, causing system crashes.

How to Resolve the Error

1. Using the Registry Editor:

• When the error message appears, press Shift + F10 to open the Command Prompt.
• Type regedit and press Enter to launch the Registry Editor.
• Navigate to HKLM/SYSTEM/SETUP/STATUS/ChildCompletion.
• On the right side, find and double-click on setup.exe.
• Ensure the Value data is set to 3. If not, change it.
• Close the Registry Editor and restart your computer.

2. Running Startup/Automatic Repair:

• Insert your Windows 11 bootable media.
• Choose ‘repair your Computer’ on the installation screen.
• Select ‘Troubleshoot’ followed by ‘Advanced option’.
• Click on ‘Automatic Repair’ or ‘Startup Repair’.

3. Formatting the Hard Drive:

Warning: This method will erase all data on your hard drive.

• Press Shift + F10 to open the Command Prompt.
• Enter the following commands one by one:
  • Diskpart
  • list volume
  • select volume 1
  • format fs=ntfs quick label=test
• Restart your computer and try the installation again.

4. Using BCEDIT Command:

• Press Shift + F10 to open the Command Prompt.
• Run the command: bcdedit /set {bootmgr} displaybootmenu yes.
• Restart your PC, access the boot manager, go to recovery mode, and restart the installation.

5. Checking Hard Disk Cables:

Faulty hard disk cables can cause this error. Ensure the cable connecting the hard drive to the motherboard is secure.

6. Disconnecting USB Devices:

Disconnect all USB devices from your system and try the installation again.

7. Updating BIOS:

An outdated BIOS can sometimes cause this issue. Consider updating your BIOS.

8. Boot into Safe Mode:

Restart your computer and hold down the ‘Shift’ key. This will launch the Advanced Startup Options, where you can select ‘Safe Mode’.

9. Update Drivers / Install Windows Updates

Ensure all your drivers, especially graphics and chipset drivers, are updated to the latest versions. Ensure you have the latest Windows 11 patches and updates installed.

10. System Restore

If you’ve set a restore point previously, consider rolling back to a state before the error started occurring.

If all else fails, try a Windows Clean Boot to see if this gets past the issue. This will start Windows with a minimal set of drivers and services. If the error doesn’t occur in this state, it’s likely a third-party application causing the issue. To do a clean boot in Windows 11 follow these steps:

1. Sign in to the computer as an administrator.
2. Select Search , type msconfig , and then select System Configuration from the list of results.
   
   
    Important: If the computer is connected to a network, network policy settings might prevent you from following these steps. Only use the System Configuration utility to change the advanced boot options on the computer with guidance from a Microsoft support engineer.  Using the System Configuration utility might make the computer unusable.
3. On the Services tab of System Configuration, select Hide all Microsoft services, and then select Disable all. Select Apply.
   
   
4. On the Startup tab of System Configuration, select Open Task Manager.
   
   
5. On the Startup tab in Task Manager, for each Enabled startup item, select the item and then select Disable. (Keep track of which items have been Disabled. You will need to know this later.)
   
   
6. Close Task Manager.
7. On the Startup tab of System Configuration, select OK. When you restart the computer, it will be in a clean boot environment. Follow troubleshooting steps to install, uninstall, or run your application. Your computer might temporarily lose some functionality while in a clean boot environment. Reset the computer to start normally after clean boot troubleshooting and resume functionality.

Personal Experiences with the Unexpected Restart Error

When I first upgraded to Windows 11, I was met with this exact error. After a few hair-pulling moments, booting into Safe Mode and updating my graphics driver did the trick. It’s a reminder that with new OS versions, staying updated is crucial.

Conclusion

While the “computer restarted unexpectedly” error can be daunting, the solutions provided above have proven effective for many users. Always remember to back up your data before making significant changes to your system. With patience and the right steps, you’ll have Windows 11 up and running in no time.

FAQs

• How do I prevent such errors in the future?
  • Regularly updating Windows, drivers, and third-party software can reduce the risk of such errors.
• Can third-party software help in diagnosing the issue?
  • Yes, tools like “WhoCrashed” can provide insights into what caused the unexpected restart or crash.
• Is it a common issue with Windows 11?
  • While not widespread, some users have reported this issue, especially after fresh installations or upgrades.
• Should I revert to Windows 10 if the error persists?
  • Before taking that step, consider consulting with Microsoft support or tech forums. Often, solutions are available without needing to revert.
• Can hardware issues cause this error?
  • Yes, faulty hardware, especially RAM or hard drives, can lead to unexpected restarts.
• What causes the “computer restarted unexpectedly” error during Windows 11 installation?
  • This error often arises when trying to restore a Windows machine to factory settings using a recovery disk.
• Is it safe to edit the registry to fix this error?
  • Yes, but always ensure you follow the steps carefully and back up your registry before making any changes.
• Will formatting the hard drive erase all my data?
  • Yes, formatting will delete all data on the drive. Always back up important files before proceeding.
• Can outdated BIOS cause this error?
  • Yes, an outdated BIOS can sometimes result in this error. Consider updating your BIOS if you suspect this is the cause.
• What should I do if none of the solutions work?
  • If the error persists, consider seeking help from a professional or the Windows community forums for further assistance.