title: error while sending mail
body: <p>I'm getting following error message when I'm trying to add a new user to site and trying to send mails to him.
  The Site is Intranet site as well exposed on internet via alternate URL mapping while adding users of local exchange group it does not give any errors but suppose that I add a user having gmail id expressed in his AD that throws following error:</p>
  
  <p>The user or users have been added successfully, but there was an error in sending the e-mail message. The server may not be set up correctly to send e-mail. To verify that e-mail is configured correctly, contact your server administrator.</p>