Hi @Michael Steven Hawk ,
Does the user in question happen to have access to other mailboxes as well? If this is the case and assuming the user is using Exchange cached mode, please try following the steps below and see if it can help:
- Go to File > Account Settings > Account settings, double click the user's account.
- Click More Settings, click the Advanced tab.
- Clear the checkbox of "Download shared folders".
- Restart Outlook and check the result.
In case the issue still persists, it's recommended to switching to Exchange Online mode and see how it goes.(Supposing the user is now using Exchange cached mode.)
If the above doesn't apply or doesn't work, I'd suggest temporarily removing the account from all other devices except from the machine with Outlook installed. This helps eliminate whether the issue is with the Outlook client itself.
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