MCMailErrorDomain error 1045

Under Window in the Menu bar select Connection Doctor.

Put all account but the one you want to test in work offline.

Select Check Again and Show Detail. This should show you what is not connecting.

To eliminate other issues in your User's folder, log out under the Apple in the Menu bar.

Log into Guest

Try adding account in Mail.

If it works, we need to look for a fix in your User's folder.

Please refer to my Post Here. It worked for me:

I keep getting "Error 1046" messages when using Mail.app to send Gmail

I hope it helps you too.

Apple defaults to just the user name but most servers what the full email address as user name. On both the sending and receiving put the full email address.

If it still balks at the password, try changing and see if a new password will work. I know doesn't make sense, but sometimes a change will work.

User Name. Enter full email address eg. UserName@doman.com

I have the exactly the same problem...no solution so far

Please give this a try and let me know if it still doesn't work for you.

I was facing the same problem. However, I have successfully resolved it. I am not sure if it works for you.

Little Background: I am using Gmail Commercial account with 2 Step Authentication.

When I checked SMTP setting I noticed that my username was given without domain name postfixed. I updated the same and now I am able to send emails without any problem.

Here is the exact location where I made the change:

Mail->Preference->Accounts->(Select Account)->Outgoing Mail Server (Drop Down)->Edit SMTP Server List->(Select Account)->Advanced->UPDATE USERNAME

Please let me know if it works for you as well.

Thanks,

HS

I already tried that... username is like test@test.com but i still get the username/password error despite user/pass is absolutely correct and works with different mail clients like thunderbird or outlook.

I'm a 1and1 user and I'm also having issues sending from my accounts. Resetting passwords didn't help, nor did resetting the accounts in Mail. I'd guess that this is an issue on their side, which isn't surprising given how sub-par their service has been for me.

Issue solved in latest yosemite dp

Hi All. I had the same issue with the error 1045. All i did was go to Prefrences - Accounts - Advance under the account i wanted fixed and ticked the Automatically detect settings, and problem solved.

Thank you for this - it worked for me

The solution for me was to explicitly enter my password in the outgoing server options. This was only effecting Yahoo and GMail and none of my other iMAP accounts and happened out of nowhere after functioning for some time. Running 10.10.3.

I am still facing this issue. Inspite of deleting the account, adding again.

Tried all of the above and still having same issue.

I'm using a private POP e-mail account through Hostgator. (So it's not a Gmail or IMAP issue)

This email account has worked for years and the issue started yesterday - wondering if it is due to the latest Yosemite update I did yesterday morning?

(I'm on a late 2008 15" MacBook Pro running Yosemite 10.10.4 )

Went to Mail->Preference->Accounts->(Select Account)->Outgoing Mail Server (Drop Down)->Edit SMTP Server List->(Select Account)->Advanced->

Tried changing port settings; didn't work.

Tried variations of user name: username@domain.com; username+domain.com; and/or simply username - none of these worked

Tried going into - applications>utilities>keychain access>passwords - deleted password for mail.[mydomain.com] (to prompt Mac to ask for password so I could re-enter new password) - didn't work.

Took all accounts offline. Put all accounts online again. (That has worked for similar issues in the past - didn't work this time)

The box was already checked for 'Automatically detect and maintain account settings' when the problem started, so I unchecked it to see if this was the issue. That didn't work.

I didn't want to delete my old account because I don't want to lose a lot of important business emails -

so I deactivated the account and set up a new account - it worked for about 12 hours and then the same error message re-appeared:

MCMailErrorDomain error 1045

(To prevent 'interference' I made sure the deactivated account is also set to use the new stmp outgoing server)

Incoming mail is fine, but it won't send outgoing mail.

I changed my domain host about a week ago - but retained the hostgator nameservers so this shouldn't have been affected. It had worked fine for a week until today.

Finally decided to re-check the box - 'Automatically detect and maintain account settings' - and VOILA it has just sent my outgoing mail!

I'm not sure what, if anything in this sequence of events has fixed the issue - or if there is some intermittent glitch at work. (Because it worked yesterday for 12 hours before stopping again)

So just watching how it goes today.

If it happens again I will go straight to Mail->Preference->Accounts->(Select Account)->Outgoing Mail Server (Drop Down)->Edit SMTP Server List->(Select Account)->Advanced-> UNCHECK "Automatically detect and maintain account settings"

then I will quit mail and re-open it

return to Mail->Preference->Accounts->(Select Account)->Outgoing Mail Server (Drop Down)->Edit SMTP Server List->(Select Account)->Advanced-> AND RECHECK "Automatically detect and maintain account settings"

I'd be curious if anyone else tries this to see if it works ... if it happens again I'll try it - and post the results here!

Back again - within an hour it wouldn't send mail again - this time because 'no outgoing server was set' ... huh?

When I went into accounts.. for some of my email accounts the outgoing server had been set to 'none'.

These are accounts where (for specific reasons) I don't want them bringing in the incoming mail, but I only use them to send outgoing mail from a specific address like admin@mydomain.com

I presume the feature to "Automatically detect and maintain account settings" had re-set all these accounts, and because there was no incoming mail server detected it had concluded there is to be no outgoing mail server?

So I reset all my mail accounts to the correct outgoing mail server and UNCHECKED the box again to "Automatically detect and maintain account settings"

I tested it and it is still working (for now)

So I'm wondering if this is a new feature?

Never had this problem before until I did the Yosemite software update 2 days ago.

We'll see how long it keeps working this time & will keep you posted.