“There was a problem while sending a test email”

SMTPSecure should not be an empty string (should be ssl or tls or none). With that value, your username/password is not even used.

Remove all code snippets that are related to the plugin filters, also make sure that no other SMTP-related plugin activated on a site. After that – try again.

I’m sorry, I’m not following. I installed the plugin, inserted my SMTP settings and ran the test email. I even disabled/unactivated all of my plugins and received the same results.

I’ve installed a template on my site. I imagine the code snippets you’re referring to would be template related? More saying that I haven’t put any code snippets in relating to the plugin filters, but my installed template would definitely have other snippets in it. Would the template be the issue?

Just for an update, I added this to functions.php in the theme to ensure SMTP secure was set to none:

add_action( ‘phpmailer_init’, ‘my_phpmailer_init’ );
function my_phpmailer_init( PHPMailer $phpmailer ) {
$phpmailer->SMTPSecure = ‘none’;
}

I get the same results with “none” selected for SMTPSecure:

Versions:
WordPress: 4.9.2
WordPress MS: No
PHP: 7.0.24
WP Mail SMTP: 1.2.3

Params:
Mailer: smtp
Constants: No
ErrorInfo: SMTP connect() failed. https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting
Host: 142.165.212.58
Port: 25
SMTPSecure: none
SMTPAutoTLS: bool(false)
SMTPAuth: bool(true)

Server:
OpenSSL: Yes
SMTP Debug:
2018-01-28 23:23:58 Connection: opening to 142.165.212.58:25, timeout=300, options=array (
)
2018-01-28 23:23:59 Connection: Failed to connect to server. Error number 2. “Error notice: stream_socket_client(): unable to connect to 142.165.212.58:25 (Connection refused)
2018-01-28 23:23:59 SMTP ERROR: Failed to connect to server: Connection refused (111)
2018-01-28 23:23:59 SMTP connect() failed. https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting

Still stumped as to why its not working.

Ok, I reviewed SMTP server on that IP address from your HOST option.

Credentials should be set, Auth should be enabled, SMTPSecure should be set to empty , like it was previously in your initial post, SMTPAutoTLS should be off.

With all that everything should be working, but it’s not. From plugin side I don’t see issues, you seems configured the plugin correctly.

Try to use the host abcmail.abccanada.ca instead of an IP address, as this IP resolved to this domain name.