Hi Marsha,
Thanks for your post. Basically, we cannot stress enough that you only have 10 days after installing Windows 11 to downgrade back to Windows 10. After that, you must perform a full reinstallation of Windows 10.
For how to downgrade Windows 11 to Windows 10, please refer toDowngrade from Windows 11 to Windows 10 - Microsoft Community
After 10 days, you need to make clean install. You can use same product key to activate Windows 10.
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). Thoroughly research any product advertised on the site before you decide to download and install it. Hope this helps.
Best Regards,
Ian Xue
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