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‎01-11-2026 06:41 AM

HP Recommended

I'm trying to figure out what's going on... c021a code indicates that some essencial process(es) gone missing. I tried using f8 to access recovery.. but it restarts again. 

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‎01-11-2026 07:15 AM - edited ‎01-11-2026 07:16 AM

HP Recommended

Create Windows 11 installation media on another PC using the Media Creation Tool or Rufus (GPT partition scheme). Boot from the USB, select "Repair your computer," go to Troubleshoot, and perform a system restore to a previous point, this should fix the C000021A boot loop issue.

 

If no restore point is available or it fails, other repair methods shown there whcih likely to fail too. In that case, if no important data exists on the drive, delete the Windows partition completely and perform a clean Windows installation.

 

In case you don't know how to boot into USB then,  Enterprises into bios at startup, disable Secure Boot (set a supervisor password if the option is grayed out), enable F12 boot menu if available, and press F12 at the HP logo to select USB; otherwise, set USB as the first boot priority

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