Sent items show twice on MAIL app

[InquiringMac]

Hello everybody!

I currently have my Outlook account setup as an IMAP account within Mail app (Version 12.2). I am having an issue where if I send out an email from the Outlook account via the Mac Mail program it shows up as it being sent twice in my sent folder. Luckily, it is sending only one actual copy.

Does anyone know how to fix this, please?

Thank you very much for your help!

Kind regards,

 

[BrianBaughn]

This has been happening since you added the account or did it work properly previously?

 

[InquiringMac]

Thank you, @BrianBaughn !

This has been happening since I added the account.

 

[BrianBaughn]

I'm not running Mojave here so I don't know if that's a specific issue with that version of macOS.

You could try deleting the Outlook.com IMAP account from your Mac and setting it up as "Exchange" to see if that makes it behave properly.