OneDrive 0x80004005 error trying to protect documents

Having some real difficulties with OneDrive in our domain. The IT department has been able to switch to it fine for Desktop/Documents/Pictures backup, but outside of IT OneDrive works properly for very few people. OneDrive just throws a generic error code 0x80004005 and refuses to backup those folders.

Odds on it working seem highest for employees hired in the last few months. Has not worked for anyone (outside of IT) that has been here for more than 2 years. Quantity of stuff in the folders doesn't seem to matter at all. Old computer or brand new computer doesn't seem to matter either.

I'm at a loss. There just aren't many knobs to turn on this thing. Ideas?