How to customise auto reply email

If you set the responder Mail to use “Use HTML content type” then you can include an image in the “Message body” of the mail using a regular HTML image tag, such as

<img src="http://example.com/image.jpg" alt="Image description" />

Please note that many email clients do not render images due to privacy and tracking concerns. Gmail, however, is an exception because they now render a cached version of your image.