We are having a very strange excel and one drive problem.
If you use the one drive icon and use the folder view files button, any excel file you click on opens in read only mode. If you open them in excel recent documents, they work fine.
What we have done:
We opened a Microsoft Case, and they examined the logs.
Then they had us remove our security agents. Same problem.
Then we removed management. And then it worked!
On our second test machine machine, we left the agents in place, and removed management and it worked again. So we're all scratching our heads.