Thanks!
I just did the same.
I had several files i was unable to access.
After a recent windows update suddenly some files were locked and showed the small brown file icon.
I am not IT literate at all.
But I just typed "OneDrive" into my Search bar on my PC, opened the One Drive App and boom.....I could immediately access all the files.
I have no idea why it happened or why it went away - but it happened after the Windows update -so maybe something happened in the update?
Hope that helps.