Hi @Lapis ,
Welcome to Q&A forum ~
Could you go to OneDrive online, download some files that take up a lot of space of OneDrive to your PC's hard drive?
If so, when the downloads are completed, it is recommended to delete those files from OneDrive online to make some free space.
And then please whether you can move files from OneDrive folder to other local folder.
Besides, I suggest you try to unlink the account first, then move files form OneDrive folder to others.
After the operation is completed, please log in to your OneDrive account again to check this issue.
Any updates, welcome to post back.
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