License key watermark on windows 10 with no reinstall or hardware changes

Question

License key watermark on windows 10 with no reinstall or hardware changes

M Vick 0

This computer has been operational for many years and suddenly is requesting a license key. We don't know how to proceed from here. It is a windows 10 pro.

20260917_165211

20260917_165226

The third error code when trying to enter a product key is "0xc0000022"

Restarting the computer briefly (~5 hrs) makes the license watermark go away.

Neil D 34,285 Reputation points Volunteer Moderator

2026-09-17T21:22:59.63+00:00

The last 5 characters showing in your screenshot are from a generic product key. This cannot be used to activate windows without a valid licence.

Did you make any changes to windows or the hardware recently.

Where did the licence you have originate. Was it part of the free upgrade from Windows 7/8.
M Vick 0 Reputation points

2026-09-17T21:29:56.61+00:00

I honestly don't remember where the license key came from as we have had the computer at least 10 years. It is strange that it doesn't have the watermark after rebooting until a few hours later.

Your answer

Neil D 34,285 Reputation points Volunteer Moderator

2026-09-17T21:22:59.63+00:00

The last 5 characters showing in your screenshot are from a generic product key. This cannot be used to activate windows without a valid licence.

Did you make any changes to windows or the hardware recently.

Where did the licence you have originate. Was it part of the free upgrade from Windows 7/8.
M Vick 0 Reputation points

2026-09-17T21:29:56.61+00:00

I honestly don't remember where the license key came from as we have had the computer at least 10 years. It is strange that it doesn't have the watermark after rebooting until a few hours later.