Apple Mail - MCMailErrorDomain error 1045

Question

inknpaper Author

Level 1

47 points

Apple Mail - MCMailErrorDomain error 1045

Incoming emails work. Outgoing emails fail. My login details haven't changed.

I empty the Outbox every time in case one email stops them all.

After a very long time of being able to send out emails, last week they suddenly stopped.

Does anyone know of a fix?

Connection Doctor doesn't really help or advise as it just gives an error message.

I have tried all sorts of variables: ports 587 & 465 with and without SSL and password on and off. It should't be that I have to change anything as it all worked before.

Thanks : )

Mac Pro, OS X 10.11

Posted on Apr 25, 2019 5:02 AM

Reply

Answer 1

Top-ranking reply

rcosta887

Level 4

3,604 points

Apr 25, 2019 5:43 AM in response to inknpaper

This issue would be a great candidate for testing it out in a new test Mac user account:

How to test an issue in another user account on your Mac - Apple Support

If outgoing mail stil doesn't work in a fresh test user account that eliminates so many possibilities and points more to an account, or server-side setting issue, or issue with your settings for your mail service provider.

If it does work in a fresh user account this points to some corruption in your main user account mail settings or saved password (i.e. Keychain corruption). In that case I would actually remove your SMTP (outgoing) server in the list and re-add it using the same values from the test account. This tells you where you can edit your SMTP server list such that you can remove it and add a new one from scratch:

Change Outgoing server settings in Mail on Mac - Apple Support

That step should really take care of it if it does work fine in your test account.

Reply

Answer 2

inknpaper Author

Level 1

47 points

Apr 25, 2019 12:55 PM in response to inknpaper

Thanks for everyone's suggestions.

It turns out that cPanel have a new compliance, and my hosting provider had updated cPanel where TLSv1.x was the root cause of the problem. I was on the phone to them for about 20 minutes where they backtracked and managed to get my outgoing emails to work. They didn't mind because they don't offer what falls under the compliance anyway.

If only they had realised the issue a few days ago, but all is well that ends well.

Thanks once again : )

Reply