The Report Message add-in works with Outlook 2016 to allow you to report suspicious messages to Microsoft as well as manage how your Office 365 email account treats these messages.
Messages that your Office 365 email account marks as junk are automatically moved to your Junk Email folder. However, spammers and phishing attempts are continually evolving. If you receive a junk email in your inbox, you can use the Report Message add-in to send the message to Microsoft to help us improve our spam filters. If you find an email in your Junk Email folder that's not spam, you can use the Report Message add-in to mark it as a legitimate email, move the message to your Inbox, and report the false positive to help Microsoft improve our spam filters.