Windows 11 system failure

Question

Helllo

I recently updated my OS to Windows 11 and soon after my PC crashed.

The pop ups are as follows:

1. Your PC did not start correctly. Restart your computer....
2. Your device ran into a problem and needs to restart.... Stop code: 0xc000021a
3. Preparing Automatic Repair
4. Diagnosing your PC
5. Then back to Your PC did not start correctly

I have tried system restore but it doesn't allow me. Please assist me.

A also would like to go back to Windows 10. How do I do that? I've never backed up anything, I just want to start afresh.

Answer 1

The boot files may have corrupted. Had you been able to reach command prompt either via troubleshoot or via the Windows installation media then there’s something we can try.

Otherwise reinstalling Windows 10 is the way forward.

Answer 2

Thank you so much. I will have to try installing Windows 10.

I can see multiple options where there is "Safe Mode" for start up but it doesn't help in anyway. It goes back to where there is 0xc000021a stop code.

I have also tried the command options but they don't lead anywhere.

What surprised me even more is a notification about 0 windows installations.

Answer 3

What options did it show?

Can you reach safe mode from the forced restart or the command prompt?

You can download the media here:

MCT/USB: https://www.microsoft.com/software-download/win...

.Iso: https://www.microsoft.com/software-download/win...

For the USB you would need to run the media creation tool & choose to create media for another PC. For the .iso you can download this & then choose whichever disc burning program you use & then choose to burn .iso to disc. You can also right click on the .iso & choose to burn image to disc I believe.

Once the media is created you should insert the media into the problem PC & reboot the PC, as soon as you see the manufacturer’s logo rapidly click the key corresponding to the temporary boot menu key - this can be F2 or F7 or F8 or F12, your PC’s manufacturer’s manual should be able to tell you that. You can then follow instructions on clean installing Windows. This will delete your personal files & programs.

If your personal files haven’t been backed up then you can try a custom clean install:

https://www.tenforums.com/tutorials/120352-cust...

You can also use the media to see if you can roll back to the previous version of Windows by using the troubleshoot option rather than the install Windows option.

Note: This is a non-Microsoft website. The page appears to be providing accurate, safe information. Watch out for ads on the site that may advertise products frequently classified as a PUP (Potentially Unwanted Products).

Please do not download any repair tool which may be offered by this site other than the ones I mention/recommend.

Thoroughly research any product which is mentioned here before you decide to download and install it.

Answer 4

It doesn't allow me to uninstall anything both latest quality update and feature update.

I don't have another PC nor a Windows 10 media. But say I was to get it, which steps should I follow.

Please advise on both scenarios.

Answer 5

Hello, I’m Virginia, I have 20 years of expertise in fixing my own & friends’ PC problems.

Sorry to hear you’re experiencing problems.

If you force restart the PC 3 times does it reach the recovery/troubleshoot options? If so then you should be able to use this to roll back to Windows 10.

Choose Troubleshoot>Advanced Options>Uninstall Updates.

If this is not possible then do you have Windows 10 installation media or have another PC on which you can create it?