Hello Norman. I'm Greg, here to help you with this.
The only reason Documents, Desktop or Pictures User folders should be in OneDrive is if they were moved there by enabling Backup Folder Protection, and then the only way to move them back in by disabling it as shown here:
https://www.tenforums.com/tutorials/116029-turn...
While there check the Settings tab that Files on Demand isn't enabled because that moves the files to the cloud with only links on the PC. I have no idea why they are settings these as defaults, but I will show you how to express your opinion on it to Microsoft later.
If you uninstalled OneDrive then you need to reinstall it from https://onedrive.live.com/about/en-US/download/, sign in keeping everything in the same place, then make those settings changes to see if they work.
If not then you'll need to try the methods here to restore the folders to default location, which may not work unless you use Option Two to rebuild them from scratch:
https://www.tenforums.com/tutorials/23504-resto...
If nothing else works he registry settings for these folder locations are here:
https://www.winhelponline.com/blog/windows-10-s...
Back up your files first! I had a case today where another guy used a hack to remove the OneDrive Explorer folder and his Documents went with them and are not recoverable in OneDrive recycle bin which is the failsafe backup for accidentally deleted OneDrive files.
Feel free to ask back any questions. Based on the results you post back, I will have other suggestions if necessary.
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