title: Cannot send user invitations and mails in bitrix
body: <p>I am trying to setup Bitrix Business Environment self hosted version in gcloud instance (CentOs7 - Bitrix Virtual Appliance V7.3.3) with Demo Licence. </p>
  
  <p>Now i am trying to add new user via invitation. I setup mailbox. I'm getting the incoming mails in Bitrix CRM application perfectly. 
  But i cannot send user invitation and emails at all. I hope it will be the problem of SMTP server setting( At administration -> Module settings -> mail shows smtp server is stopped ) </p>
  
  <p>How can i setup SMTP server in Bitrix ?? 
  if anybody here familiar with Bitrix Please help me.</p>
  
  <p>All helps are appreciated.</p>