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And the choose Automatic replies from the list that appears on the left:
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To set an automatic reply for a mailbox that you have access to but is not your primary mailbox, first Need to update the out of office or autoreply for another mailbox? First connect to that mailbox using the steps found here:
https://royalroads.atlassian.net/wiki/spaces/ITKNOW/pages/5833646/Open+a+Shared+Mailbox+Using+Outlook+Web+Access
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