Actionmailer says email sent but it never gets there (Rails 3) - ruby-on-rails

Question

Actionmailer won't send emails in development, even though they say 'sent' in the console.
gemlist:
gem 'send_grid'
development.rb:
config.action_mailer.perform_deliveries = true
config.action_mailer.default_url_options = { :host => "localhost:3000" }
setup_mail.rb:
ActionMailer::Base.smtp_settings = {
:address => "smtp.sendgrid.net",
:port => '587',
:domain => "heroku.com",
:user_name => "app123456789#heroku.com",
:password => "asdfasdfasdf",
:authentication => :plain,
:enable_starttls_auto => true
}
app/mailers/user_mailer.rb:
class UserMailer < ActionMailer::Base
include SendGrid
def registration_confirmation(user)
#user = user
mail(:to => user.email, :subject => "Registered", :from => "media#myemail.com")
end
end
app/views/user_mailer/registration_confirmation.html.haml:
Confirm your email address please!
= accept_invitation_users_url(email_token: #user.email_token)
console:
Sent mail to alain#myemail.com (656ms)
Date: Tue, 11 Feb 2014 13:35:11 -0500
From: media#myemail.com
To: alain#myemail.com
Message-ID: <52fa6d5f667ea_27ce5564820279f3#Ice-box.mail>
Subject: Registered
Mime-Version: 1.0
Content-Type: text/html;
charset=UTF-8
Content-Transfer-Encoding: 7bit
X-SMTPAPI: {}
Confirm your email address please!
http://localhost:3000/users/accept_invitation?email_token=_JL8DQ2GItxl
Redirected to http://localhost:3000/
Completed 302 Found in 1396ms (ActiveRecord: 192.2ms)

Answer 1

you can try setting:
config.action_mailer.raise_delivery_errors = true
to see if it raises any error on delivery. Otherwise try using other email or check it in you junk folder
Or try this in development mode to check if there is any issues there(it seems fine as you can see the confirmation in the console)
https://github.com/ryanb/letter_opener

Answer 2

Add config.action_mailer.raise_delivery_errors = true to production.rb or development.rb and restart your app to make the changes working

Answer 3

Put this before your smtp settings:
config.action_mailer.raise_delivery_errors = true
Add ".deliver" at the end where you are calling the email method i.e.:
UserMailer.welcome_email(#user).deliver
It will raise exception that will help you to find the failure cause.
If you are using background job to send email, You can put this snippet in exception block and use ExceptionNotification gem to send email with details which will help you to catch and find the reason of failure easily.