Rails 4: Net::ReadTimeout when calling ActionMailer

After reading this post I took another look at my smtp settings and added

tls: true 

changed port: 465 to port: '465' as I noticed that most people write it as a string. Also Similarly changed the string "plain" to the symbol :plain

I faced the similar issue when i connect the smtp mail to qq mail(business mail). I updated my settings by following the post as like below:

config.action_mailer.smtp_settings = {
address:              'smtp.exmail.qq.com',
port:                 '465',
domain:               'groobusiness.com',
user_name:            ENV['GMAIL_USER_NAME'],
password:             ENV['GMAIL_PASSWORD'],
authentication:       :plain,
enable_starttls_auto: true,
openssl_verify_mode:  'none',
ssl:                   true,
tls:                   true
}

And the issue got solved. Hope it might be helpful for someone who is facing this issue.