Any properly licensed / activated Windows 10 computer can be upgraded or clean installed to Windows 11 provided the following occur:
a) if the Windows upgrade assistant is used it must pass the compatibility check to have a supported upgrade
b) if the Windows upgrade assistant is used it can fail the compatibility check and still be upgraded if the registry and files are modified so that they are not detected by the Windows upgrade assistant. (these methods were reported on multiple websites) (computers with unsupported windows 11 upgrades / installations may not benefit from the improvements in performance and security. And the unsupported installations may have problems with Windows updates and / or Microsoft Defender updates)
c) if important files are backed up to another drive or the cloud then clean installs can be performed
Multiple websites have reported clean installs of Windows 11 on very old computers.
These included desktops, laptops, and tablets.
If a Windows 10 computer has ever been updated then the licensing data is on Microsoft servers.
This enables end users to replace disk drives or clean install Windows 10 or Windows 11.
If end users choose to upgrade Windows 10 to Windows 11 there is a default 10 day rollback period.
This can be modified during the 10 day period to up to 60 days.
In addition end users can use third party software to make free backup images.
Then at anytime the image can be restored.
So backup images of Windows 10 enable end users to use Windows 11 for any time period and then return to Windows 10.
They will return to the exact moment in which the image had been made.
These are free and pay methods for backup images:
Acronis, Aoemi, EaseUS, Macrium, Paragon
These are links that may be useful:
https://www.elevenforum.com/t/clean-install-windows-11.99/
https://support.microsoft.com/en-us/windows/reactivating-windows-after-a-hardware-change-2c0e962a-f04c-145b-6ead-fb3fc72b6665
https://support.microsoft.com/en-us/windows/using-the-activation-troubleshooter-d717cdff-cf19-9770-7198-40119c2a696c
https://support.microsoft.com/contactus
https://www.elevenforum.com/t/change-number-of-rollback-days.1543/
https://www.tenforums.com/tutorials/61026-backup-restore-macrium-reflect.html
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