Activation error 0x803F7001: causes and fixes

BySmart Keys

Windows found no valid licence for this PC. It often appears after a hardware change or clean install.

When it appears

  • After replacing the motherboard.
  • After installing a different edition from the one licensed.
  • On a new installation with no key.

How to fix it, step by step

  1. Open the Activation page and run Troubleshoot.
  2. Choose “I changed hardware” if that applies and sign in.
  3. If you have a key, use Change product key.
  4. Check the result on the same page.

Home installed instead of Pro

Laptops with a firmware Home key often install Home. Enter your Pro key to switch, or see how to upgrade to Pro.

Windows 11 HomeWindows 11 Pro

Can I keep using Windows with this error?

Yes, with limits. See [what happens if you do not activate Windows](what-happens-if-you-dont-activate-windows/).