Today I discovered a whole pile of messages in my “On my Mac: Outbox” and no matter what I tried I couldn’t get them to send. I use gmail as my mail server. The emails looked like they were sending – there was no error message – but they didn’t actually send. They were still in the outbox. When people started to complain about my slow email replies, I looked and discovered all the emails over the past three days were just sitting there in my outbox!
I checked out the Apple help page here and tried what they suggested. According to the Apple mail connection doctor everything was working fine – I got all green ticks!
I did a Google search and on different forums found all sorts of ideas:
None of these solutions worked!
Warning: Do not try moving them to ‘gmail outbox’. They will be permanently deleted. (I thought that if I move them to Gmail outbox then they might send – unfortunately they just disappeared!)
In the end I found this forum from 2012 where someone was suggesting changing DNS settings. This is a very strange because Safari is working fine which means my DNS is working fine. I can even receive emails! Even namebench was working fine.
But sure enough I changed my DNS settings and the problem fixed itself! This problem has been round since 2012! And the solution still works!
Here’s how to do it:
Go to the advanced tab of the network control panel in system preferences and click on DNS. You will probably have the DNS settings for whichever Internet provider you use.
I put in the google DNS numbers 18.104.22.168
I restarted mail and the problem was fixed.
I didn’t want to use the Google DNS, so I went back and put in my original DNS settings – the problem reappeared!
So for some reason, at the moment, Apple mail is only sending messages through Gmail if I use the Google DNS server. I am seeing this as a temporary fix, not a solution. I don’t understand why this works at all.