Hello,
Thank you for posting in Q&A forum.
There are some steps that we can try:
1.Check your account type and set it as administrator if it's not.
2.Disable user account control to ensure you have full control over your system.
3.Check if there's any group policy that block the change.
4.Back up important files before reinstalling a clean Operation System.
I hope the information above is helpful.
If you have any questions or concerns, please feel free to let us know.
Best regards,
Jill Zhou
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