This article will explain what the error '8004020f' is and how to resolve it.
The error '8004020f' is caused when you try to send email from an email address that is not set up on your server and the website has a dedicated IP address.
Example: You are sending an email form from the email address firstname.lastname@example.org however sales@ and John@ are the only two email addresses you have set up.
Change the from email address to an email account that exists on your server or create a new email account for the required email address.
If you are using multiple addresses use ";" or "," to separate the addresses.
Check you have configured the mail settings for your server correctly.
If you are using a firewall make sure your web server is set to pass through it correctly.
Change your SendUsing value from 2 (port) to 1 (pickup).