Just SMTP

This module allows Drupal to send emails through an SMTP server with optional authentication It is designed to have just the minimum required functionality to do that.

Note that for most hosting environments you do not need this
module. Hosting environments like Pantheon require use of modules like
this though.

Requirements

• Access to an SMTP server
• PHPMailer installed as library.
• Optional: To connect to an SMTP server using SSL, you need to have the openssl package installed on your server, and your webserver and PHP installation need to have additional components installed and configured.

Installation instructions

1. "git clone" the latest PHPMailer under sites/all/libraries.
2. Install the libraries module.
3. Login as administrator and configure the module
   (/admin/config/system/just_smtp).
   You must turn it on explicitly.

Testing

The module has been tested with the reroute_email module, and both
work correctly together.

Comparable modules

Drupal has an SMTP module, but unfortunately was broken for me,
#1044534: Improve support for multipart/mixed messages. Fixing this appeared to be very hard as the SMTP module contains a half-baked MIME parser which I didn't want to fix. It also simply has way too many options for what its purpose is.