Drupal - PHP SMTP设置正确但电子邮件不会发送

I get the following error when my Drupal site tries to send out a welcome email when users are signed up: Failed to connect to mailserver at "secure.emailsrvr.com" port 465, verify your "SMTP" and "smtp_port" setting in php.ini or use ini_set()

I at first set the following in PHP.ini:

 SMTP = secure.emailsrvr.com
    SMTP_PORT = 465
    sendmail_from = support@managerspitstop.com
    username = support@managerspitstop.com
    password = ****

But I still got the error above so I added the following into the mail.inc file which is a file within the Drupal site:

 ini_set("SMTP","secure.emailsrvr.com");
    ini_set("smtp_port","465");
    ini_set("username", "support@managerspitstop.com");
    ini_set("password", "*****");
    ini_set("sendmail_from", "support@managerspitstop.com");

But still get the same error. So I contacted Rackspace who I have set up the email with and they have told me the settings I am using are correct. To test this I added the email to Outlook 2013 send out and email and received an email just fine.

I have looked around and couldn't find a solution. Any help will be greatly appreciated.