Once you add Online Form on your website, please make sure to set Email Setup for the Online Form properly by this guide (a must).

If you're here because you set it properly but it doesn't work, please contact your host provider to allow following requirements in their server for you.

1. Enable proc_open() extension in WHM (root) -> PHP ini: 

1) Set allow_url_fopen = on

2) Remove proc_open from disable_function

2. Enable TCP_OUT = 465 in WHM > Plugins > ConfigServer Security & Firewall > Firewall Configuration.

This will fix the problem on Email is not sent from Online Form.

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