When I was testing my app on my development machine, I had my app configured to send email via SMTP. When I deployed it to the host (site5), email stopped working.

Changing the email protocol in my environment.rb file to sendmail fixed this issue.

environment.rb:

...
Ericbt::Application.configure do
...
  config.action_mailer.perform_deliveries = true
  config.action_mailer.raise_delivery_errors = true
  config.action_mailer.delivery_method = :sendmail
end

# Initialize the rails application
Ericbt::Application.initialize!

...