mail stuck in outbox, general mail problems

Just to say thanks. This worked a treat. I actually copied my Outbox emails into Gmail online and sent them, deleted them and then I didn't need to do the two stage opening and closing of iMail. Thanks for the simple instructions.

Thank you! vaheasalnyan helped me. I unchecked the enable this account and then rechecked it and my mail started going out. Thanks!

I am quite surprised this problem still exists in Mail 9.0 under OS X 10.11.

At some point Apple needs to seriously address this issue with outgoing mails getting stuck, especially if they include attachments. These stucked mails don't only just get stuck, they also block the entire online connection on the Mac. Even Skype goes offline with these stucked mails.

I installed Little Snitch to see the current data traffic in the menu bar or in the Little Snitch Network Monitor - the Little Snitch Network Filter itself is turned off to make sure Little Snitch is not causing the mails to stuck. It's interesting to see that the stucked mails block the online connection for other applications while Little Snitch shows only very small amount of kB/s being transferred - you can also see this in the Activity Monitor app.

How can Mail eat up all online traffic with these stucked mails if there is actually almost no traffic? I close Mail and my other online connections operate normal again. I open Mail with its stucked mails in the pipe and all other apps go offline again while only a few kB/s are being up- and downloaded. This is 100% reproducible.

I understand that it would take a while to transfer attachments of a few megs when Sent Messages and Draft Messages need to get stored on the server (this is a setting in the account settings). In this case I should see high upload traffic in Activity Monitor or Little Snitch and as we know high upload traffic would affect other online activities such as surfing or even Skype. But why do other online connections get affected with only a few kB/s of traffic from stucked mails? Why does Mail block the entire online connection?

Use Gmail - nothing gets stuck there, and it's a free service, unlike Apple $$ hungry.

Turn off cellular data for mail. Wifi too. Then turn off phone. Turn on. Go to mail. It'll have red exclamation in email stuck in outbox. Edit and swipe to delete The message that is stuck. It should finally delete.

TUrn cellular and wifi back on.

THis his worked for me.

Sent emails are going to my outbox

Cool man, how can it be so easy sometimes, thousands of programmers sit in silicon valley and dream and just don't get it. Thanks!!!!