Connection refused - connect(2) for "localhost" port 25 rails

First of all, when developing on localhost, it's common to not actually send out mail, rather to treat that as a deployment detail and stick with the Rails default behavior which is to spit out the mail headers and contents into the console STDOUT (where you can verify that the text looks right). Is there a specific reason why you need to test sending messages in the dev environment?

Secondly, you mentioned that you set the SMTP settings in both development.rb and environment.rb. You shouldn't need to set these settings twice; in general I'd use development.rb for settings specific to the dev environment, and environment.rb only for settings that will always apply to all environments (dev, tests, and on the live deployed server). So if you're setting the same settings in both development.rb and environment.rb, I'd start by removing one or the other; redundancy will only make your job harder down the road.

Finally, to troubleshoot this I'd start by asking Rails what its settings are rather than waiting for the mail delivery to fail. Try the following:

• Start up rails console
• Enter Rails.configuration.action_mailer.smtp_settings and compare the resulting hash against your expectations. This hash should contain the port and domain settings that are used when sending out all mail (in the current environment), so if ActionMailer is trying the wrong port then I'd expect the port to be wrong here too.

Where are you setting $SMTP_SERVER, $PORT and $MAIL? Is there any reason you aren't using Rails' convention for environment variables, ENV['SMTP_SERVER'] etc.?

Hope some of that helps. Good luck!

replace

config.action_mailer.delivery_method = 'smtp'

with

config.action_mailer.delivery_method = :smtp

Ensure your Rails.configuration.action_mailer.smtp_settings is symbolized keys

The app might be using mailcatcher gem for all outbound emails on development, which you haven't installed or don't have running. At least that was my issue. Check out https://mailcatcher.me and follow the instructions given.