Muse Emailing Form not Working - "PHP error"

Okay, so it sounds very familiar to this topic

In which case, you will need to download the latest version of PHPMailer

Once you download it, extract the folder inside the zip file and upload it to your server with your other PHP Files (the entire folder).

Then you will follow these instructions (click the down arrow to see it properly without having to navigate to the other topic)

Since you will be uploading the folder, your require statement will be require 'PHPMailer-5.2.13/PHPMailerAutoload.php';

The rest of the changes will be you putting in the correct SMTP host, username and password (along with the appropriate From and FromName.