Once inside the cPanel Control Panel, click on the "Auto Responders" section in the Email Menu. Depending on the skin you are using, this menu will be shown as "Email" (X skin) or all of the sections of the menu will be presented in a neat table (X3 skin)
1. In the "Auto Responders" section, you will see that the fields are empty, since you haven't defined anything yet. Click on the "Add Auto-Responder" button to create a new one.
2. In the new page, you will see all the fields you have to fill in to set an auto responder.
Character Set - Define the character encoding for your message. If you are not sure what this means, just select UTF-8
Email - Set the email, for which the auto responder should be active. If the email is not present, the auto responder will still be created and will reply to incoming messages. The messages, however, will be discarded and will not be kept on the server.
From - Specify from whose name you want the reply to be.
Subject - Enter the email subject.
Body - Enter the message that will be sent. In the body of the message, you can use the %subject%, %from% and %email% tags. These tags will copy information from the sender's message, such as its subject, and from the email headers, or the message body in the case of the %email% tag, allowing you to use it in the auto responders message.
3. When you have filled everything, click on the "Create/Modify" button and you're done!
You can test if everything is working by sending an email address to the email you have activated the auto responder for.