Often (too often), OneDrive on Windows gets confused and creates errors in the file system.
The result is that some files appear to be locked; in reality the situation is even worse.
Trying to delete them, you get the error "The tag present in the reparse point buffer is invalid".

The solution for to open a prompt with Administrative privileges and execute:

chkdsk c: /f

The fix of the file system will be done at the next reboot of the computer.