Hi Martin -
We solve problems here every day by replacing a corrupted User account which is not usually reparable. This is a simple process which only involves moving the files over, since apps are already installed for all accounts anyway. So since you confirmed this already, to move over to test for account follow these steps:
Make it an Administrator account if you want user to be able to make changes: https://www.digitalcitizen.life/change-type-use...
Sign into the new account, test it works correctly, if so to Move the files into the account via C:\Users. When you choose the old User account it will grant Admin permissions to each folder and file as a green bar travels across the address bar, this may take a few minutes and then the User data folders will open.
Open each User folder, from Home tab choose Select All (or press Ctrl + A) , then Copy (or Ctrl + C). Then go to the new Account's corresponding folder to choose Paste (or Ctrl + V). Do this for each folder.
When ready delete the old account in Settings > Accounts > Family & Other Users, or if you want to save it just change it to a Local Account in Settings > Accounts > Your Info > Sign in with a Local Account Instead.. Test for
You can then change the new account to the Microsoft account if desired:
https://www.tenforums.com/tutorials/5375-switch...
Feel free to ask back any questions. Based on detailed results you post back I will have other suggestions if necessary.
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