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Action

Add a shared mailbox you have permissions to access

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using the Outlook mobile app for Outlook for iOS or Outlook for Android.

Instructions

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See Microsoft's steps at Add a Departmental (shared) Mailbox to the Outlook Mobile app for iOS or Android

Additional information

Currently, there is no supported way to add a Departmental Mailbox to a mobile device's native mail program.  However, there is a workaround to access a Departmental Mailbox via your device's browser (Safari, Chrome, etc.):

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