When encountering these Onedrive sync issue errors with Office 365 applications like Excel/Word on windows 10 such as:

Sign out and then sign back in to work or school account to re-register device with Office365 account.

- type "connect to work or school" in the windows 10 search bar

- choose the account that you are having an issue with and click on "disconnect"

- sign back in to the same account by clicking on "connect" and re-entering credentials

M6iT Support Services