Following works for me. In the “Search Current Mailbox (Ctrl+E)” box, type: read:no and hit Enter .
When it shows “Find More on Server” link, click it. Then the unread email(s) should appear.
ED.....
[Outlook 2013] How to fix the wrong number of unread emails flag in Outlook 2013?에 대한 요약내용입니다.
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