Email notification failure

[matt (support)]

To see if your ISP is blocking your request, you might want to try this from Terminal (just to see if it connects);

telnet sub5.mail.dreamhost.com 465

-bash: telnet: command not found
Looks like High Sierra ditched telnet?

No telnet available in High Sierra, so I tried ssh. It connected. In summary here is where I am....

Setup action group to test simple email send to my gmail address
I get email send authentication failed
Using port 465 which Comcast they don't block
My mail server is at Dreamhost. It is sub5.mail.dreamhost.com
I have webmail on the server. I was able to log in.
I sent an email to the server and then used Indigo to scan for it. It found the email.
Nothing has changed on my end
Chatted with Dreamhost. They said nothing has changed on their end.

Any ideas for further diagnosis?

Do you have a firewall enabled on your Mac? Maybe it's allowing 465 for your browser but not for Indigo?

Alternatively, just for grins, you could install the BetterEmail plugin and see if it can send using Dreamhost. That would point towards some bad data saved in the Indigo preferences.

Thanks for your interest in this problem. The firewall is on, so I added Indigo to the list. Restarted Indigo and tried to send a mail again. Still got the authentication failure. I saw your email post of settings needed for BetterEmail and they are identical to what I have set for Indigo. Again, POP works with Indigo from same server, so the problem is unique to smtp. The settings I have are the same as I have had for some time, and it was working before. I double checked the password and used it to log into webmail on the server. This suggests something is wrong on my end, but I can't find anything.

Try shutting down Indigo, then open the "Indigo Server Prefs.indiPref" file in the Preferences folder. Just use a text editor like TextWrangler or BBEdit. Then search for "smtp". Look for any odd characters. The password is semi-encrypted so it won't look like you expect, but check the other fields.

Problem resolved. Thanks for the tip to look at the smtp fields in Preferences. One of them looked strange. It had an extra space. That was the problem. No idea how the space got there, but anyway problem resolved. Thanks very much for the good advice.

I hate to bounce this old thread, but I ran across it trying to solve another email problem I had and hoped posting my solution might be helpful to some.

Both the internal email and the Better Email plugins when running on El Capitan will run in to issues where the SSL security has been upgraded fromTLS1 to TLS2 on the mail server you're connecting to. The OpenSSL that comes with El Capitian only support TLS1. So if your mail server has been upgraded to only support TLS2 or later (which is a current security recommendation), you will run into this issue. Your work around is to either 1) get the main server to support TLS1 again or 2) turn off StartTTL/SSL altogether or 3) Upgrade to a newer OS.

Hopefully this has been useful to some!