If you are using Opencart on a VPS or dedicated server and you have cPanel/WHM with Configserver Firewall (CSF) installed, you may encounter a problem when sending email.

If you check error log, you may see the similar error.

PHP Warning: fsockopen()  [function.fsockopen'>function.fsockopen]: unable to connect to ssl://smtp.gmail.com:465 (Connection timed out) in /home/XXXX/public_html/www.example.com/system/library/mail.php on line 153

You may try the following fix.

1. Logon to WHM & browse to ConfigServer Security & Firewall page.

2. Click on “Firewall Configuration” button

3. Find “SMTP_ALLOWUSER” option.

4. In the field add your cPanel username. If the is multiple username use comma to separate.

5. Click “Change” and Restart Configserver Firewall

This guide may fix other program such as Interspire Email Marketer as well.