Flag outgoing emails not working properly on Outlook for Mac

This is actually a known limitation in the new Outlook for Mac. When you flag an outgoing message, Outlook currently applies the flag to both you and the recipient, and there’s no option yet to flag it just for yourself. The best workaround is to send the message first, then go to your Sent Items folder and flag it there, that way, the flag only appears in your mailbox and not for the recipient. Unfortunately, Microsoft removed the “Flag for me only” option that existed in the Classic Outlook, but many users have requested that feature back. If you’d like, you can send feedback directly from Outlook under Help → Feedback to add your voice to those requests.

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