Why are send messages are showing up in my inbox?

Send messages are emails that are sent and received just like any emails from Outlook or other apps. If you would like to view and respond to Send messages only from the app, you can create an Inbox rule to move these messages to another folder. More details on creating an inbox rule can be found in this article - https://support.office.com/en-za/article/Manage-email-messages-by-using-rules-c24f5dea-9465-4df4-ad17-a50704d66c59.
 

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