Defining ‘WPMS_SMTP_USER’ returns blank value

Hi there!

Great work with this plugin, we find it works really well.

We have come across an issue however when we are defining SMTP settings in wp-config.php.

Everything is pulled in, except for ‘WPMS_SMTP_USER’; this remains blank. When it is defined, the SMTP username is disabled within WP Admin area, but remains empty and no value is sent during the SMTP auth stage. Is there something we are missing?

An example of what we are defining in wp-config.php is below:

$smtp_username = ‘testuser’;
$smtp_password = ‘testpass’;
$smtp_host = ‘testhost’;

define( ‘WPMS_ON’, true );
define( ‘WPMS_SMTP_HOST’, $smtp_host);
define( ‘WPMS_SMTP_PORT’, ‘587’);
define( ‘WPMS_SSL’, ‘TLS’);
define( ‘WPMS_SMTP_AUTH’, true);
define( ‘WPMS_SMTP_USER’, $smtp_username);
define( ‘WPMS_SMTP_PASS’, $smtp_password);

Using PHP 7.1, WP SMTP Plugin version 1.3.3.

Thanks in advance