SMTP module doesn't send an email


I’m working on Drupal 8, PHP -7.0. I have installed the latest version of SMTP module which throws a below error when trying to send an email. 

  • SMTP module is active.
  • A test e-mail has been sent to [email protected] via SMTP. You may want to check the log for any error messages.
  • The configuration options have been saved.

Warning message

Disabled fields are overridden in site-specific configuration file.

Error message

Unable to send email. Contact the site administrator if the problem persists.

I’m using the below configuration and entered the correct username and password


SMTP port: 465

Use encrypted protocol: SSL


The below error in the logs:

Error sending email (from [email protected] to with reply-to not set).

Message Error sending e-mail from [email protected] to [email protected]: SMTP Error: Could not connect to SMTP host.

Help is appreciated. 

Thanks in advance!

Drupal version: