Do you have sendmail installed on your development machine? Try this on the command line:
which sendmail
If I were you, I would not send emails in development mode, but if you want to do this, register with your gmail.com account and use this:
config.action_mailer.delivery_method = :smtp config.action_mailer.smtp_settings = { :enable_starttls_auto => true, :address => "smtp.gmail.com", :port => 587, :domain => "gmail.com", :authentication => :login, :user_name => "<your username>@gmail.com", :password => "<your password>", }
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