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You can figure out whether you are using Outlook Classic or Outlook New by the top task bar on the top of the window. Classic will have a File tab, while New will not.
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If you’re using the Outlook Classic Outlook, please follow the instructions for adding a shared mailbox to Outlook (Classic) instead. |
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You can view the shared mailbox under “shared with me“ option.
Outlook New does not support offline cache. So. there is no need to disable it or worry about duplicate responses and calendar conflicts.