Starting on October 15th, the IT Support Centre started to receive an increased number of calls about OneDrive for Business failing.

Users have reported red X's beside their files and the client reports sync errors are present. Attempts to repair the sync fail.

Microsoft is aware of the problem and report that not all customers are affected. They are currently preparing a fix.
If you are experiencing this problem, please contact the IT Support Centre or submit an online help form as we would like to track the extent of the problem and to ensure the fix is applied when available.