SMTP URI and logging

Using SMTP protocol to transfer emails ensures solid operations.
It is very easy to set up SMTP. You can find the settings for this plugin at the bottom of WordPress admin menu Options / General.

You should get your SMTP settings from your ISP, hosting provider, webmaster, email provider etc.

Using every option SMTP URI formally looks like this:

smtpTLS://USERNAME:PASSWORD@HOST:PORT 

Thus encryption type and :// and user name and : and password and @ and mail server name and : and port number.
All except encryption type and mail server (host name) are optional.

SMTP encryption types are as follows:

• For encrypted connection (STARTTLS on submission port) start your SMTP URI with smtpTLS:// – the default port is 587.
• For fully SSL encrypted connection (SMTPS) start it with smtps:// – the default port is 465.
• For unencrypted connection (plain SMTP) start it with smtp:// – the default port is 25. This is not recommended for non-local servers.

WARNING! Use URL-encoded strings.

You can find the settings for this plugin at the bottom of WordPress admin Options / General.

You may define your SMTP URI also in wp-config.php:

define( 'SMTP_URI', 'smtpTLS://USERNAME:PASSWORD@HOST:PORT' ); 

To set From: name and From: address use
WP Mail From II plugin.

SMTP error logging

SMTP communication errors are logged in PHP error.log and – if
Sucuri Scanner
plugin is available – are sent to Sucuri and can be viewed in its Alert Logs panel.

Adding automatic Bcc: address

An automatic Bcc: address can be set by adding path to SMTP URI: /admin_email.

SMTP debugging

Add query string to SMTP URI: ?debug.

Debug level can be set by adding a value: ?debug=4, possible values: 0,1,2,4

TODO

• Option to skip newsletters: ALO Newsletter, Newsletter, Mailpoet.
• Video on installing and setting up this plugin.
• Remove smtp_uri option on uninstallation (I hope you won’t uninstall it)

Usage examples

Unauthenticated local SMTP server on port 25

smtp://localhost 

Unauthenticated local SMTP server on submission port

smtpTLS://localhost 

Authenticated connection to localhost on port 25

smtp://john.doe:Secretpwd1@localhost 

“@” sign in the username, a Gmail example

smtps://your.address%40gmail.com:[email protected] 

Sendgrid example

smtpTLS://CREDENTIAL-USERNAME:[email protected] 

Mandrill example

smtpTLS://REGISTERED%40EMAIL:[email protected] 

Unauthenticated SMTP server on a custom port

smtpTLS://mail.server.net:2525 

Development goes on on GitHub.