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https://support.microsoft.com/en-us/help/290846/how-to-use-the-out-of-office-assistant-in-outlook
For Mac Users with Outlook for Mac on the Desktop
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For Those Using Third Party Clients or Outlook Web Access (OWA) Users
For Shared Mailboxes
Users of Outlook for Mac 2016 or newer can use Outlook to ass these settings.
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