Hi @Chris ,
Did you know the version number of OneDrive you're using?
I suggest you try 2 methods to help you test this problem:
- install the latest updates for OneDrive and check if you can add the new account.
- remove OneDrive from Mac and re-install the initial version and check test the result.
Test these 2 methods and we can confirm if this problem is related to iOS update or OneDrive updates.
Any updates please let me know and I'm glad to help you.
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