OneDrive file opening troubleshoot
Solution
File has a long pathname
If the pathname is greater than 218 characters, but less than 400 characters, try opening it online through the browser. Then shorten the name or move the file in order to get the pathname to less than 218 characters. This is due to Windows limitations. The file may just not open, open with error or open in Read-Only mode. It varies with version of Office and which Office application being used.
Status Column Missing
If the status column (the cloud icons, etc to the right of the file name) does not show in File Explorer, then the OneDrive Service is not running. This could be due to OneDrive being prepared for upgrade, but awaiting restart. Open up OneDrive client app and plan to restart once you can. It can also occur if the user is not signed in.
Environment