Troubleshoot email on a new Discourse install

If you’ve just installed discourse, but email doesn’t seem to work. Unfortunately this means you can’t log in as an admin to finalize the install. 

Try the doctor

cd /var/discourse
./discourse-doctor

It will check several ways that your mail configuration might be broken, and offer advice. Try that first.

Did you enter email settings correctly?

The simplest way is to run ./discourse-setup again. Did you enter everything correctly?

You can also double check the settings in your containers/app.yml file. A valid email section looks like this:

DISCOURSE_DEVELOPER_EMAILS: 'name@example.com'
DISCOURSE_SMTP_ADDRESS: smtp.mailgun.org
DISCOURSE_SMTP_PORT: 587
DISCOURSE_SMTP_USER_NAME: postmaster@discourse.example.com
DISCOURSE_SMTP_PASSWORD: aUd34cdWKCu6CTjfoH7ykk

Closely examine all values for correctness. Note that it all aligns, there are no leading # characters, and there are single quotes around the developer email field.

If you had any errors in your app.yml and made changes , you MUST rebuild the container for those changes to take effect!

cd /var/discourse/
./launcher rebuild app

Well, you don’t always need to rebuild

Doing a rebuild will often fix things that seem broken, but it takes a while. There are times when a full rebuild is not necessary; the above is usually the best advice, but If you change just SMTP settings, you can do just this to apply them without doing a full rebuild:

cd /var/discourse
./launcher destroy app
./launcher start app

Are your SMTP connections being blocked?

To confirm that your server can indeed contact the email server, issue this command:

telnet smtp.mailgun.org 587

If you can’t connect this way, you’re almost certainly blocked. (And if you do get connected, the escape character for SMTP is ctrl+], then use quit to exit telnet.) If this happens, contact your cloud provider support and confirm that your email connections are not being blocked.

What do the Discourse logs say?

From the command line, issue this command:

cd /var/discourse
tail shared/standalone/log/rails/production.log

This will show the last few lines of the log. Look for anything mail related. If you need to view the fuller logs, try

more shared/standalone/log/rails/production.log

To page through the complete log by pressing space. Look closely for any email related message

Src:
https://meta.discourse.org/t/troubleshoot-email-on-a-new-discourse-install/16326