Rails EOFError (end of file reached) when saving a devise user

I'm getting this error in production when trying to create a user (i'm using the devise gem).

EOFError (end of file reached):

I hit this problem before and it was due to my smtp settings using zoho mail.

I believe my configuration below is what fixed the problem:

ActionMailer::Base.delivery_method = :smtp  
ActionMailer::Base.smtp_settings = {            
  :address              => "smtp.zoho.com", 
  :port                 => 465,              
  :domain               => 'example.com',   
  :user_name            => 'user@example.com',
  :password             => 'password',         
  :authentication       => :login,
  :ssl                  => true,
  :tls                  => true,
  :enable_starttls_auto => true    
}

Now we've added SSL to the site and I believe that is what is causing this error to occur now.

Does anyone have any insight into this error or zoho mail smtp settings with SSL?