Devastating Apple Mail Problem

I have a Yahoo Mail account I use very casually. It is not my main account.

I have been having ongoing computer problems, so I have re-entered all my Mail account information, including Yahoo, more times than I would care to reveal.

On current Macs, if you delete the Yahoo account, when you re-enter it, Yahoo is a special case. It appear that although you enter your Password, Yahoo converts it immediately into a token-and-certificate validation.

One theory is that you are still relying on older validation methods that Yahoo has deprecated, and it is actually refusing your sent emails. So not a Mail problem, not a Yahoo problem, but a cooperation problem.

I recommend you make careful note of your Yahoo mail password, and delete and re-enter your Yahoo Account. Depending on what version of MacOS you are running, that may invoke Accounts preferences (from Mail preferences) to do the login re-entry.

If they are sent and never received then you are sending them to the wrong but an actual address. They are going to someone if they are sent without an error message. Check the address you are sending to. Try sending yourself an email to see if you get it.

Make sure "Mail.app" is selected as: Default email reader in Mail > Preferences > General.

Readers have previously reported that they do NOT get the whoosh sound, and their supposedly sent emails are languishing in their "Outbox" folder, waiting to be sent. That one, we know how to go about fixing.

But if you get the whoosh, and they disappear, they HAVE been sent as far as Mac Mail thinks.

What are you using for an email provider?