Hi @ Missy Evenson
Welcome to our forum!
According to my research, I found that new emails are not updated in real time in New Outlook, you may please manually sync your shared mailbox (View>sync).
If this doesn't work, you may please continue with the steps below:
- Does the issue also occur on the Classic Outlook? If so, please you log in to the Outlook for web, add the shared mailbox (Click ‘…’ on the left of the Folder >Add shared folder or mailbox>Add the shared mailbox) and check if the same issue persists.
- If the issue still exists, you may please check your permissions and ensure you have the correct access rights to the shared mailbox and its folders.
- Otherwise, it is suggested that you remove (Right click shared mailbox folder>Remove shared mailbox) and re-add the shared mailbox in New Outlook.
If all above do not work, considering data file corruption, it is proposed that you create a new profile, re-add your account to the new profile and check if the same issue still occurs.
Hope it helps!
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