Customizing the Confirmation Page
The confirmation page appears after a successful transaction. It is composed of a Page Template wrapper, fixed content and a configurable area. The Confirmation Page tab contains the content of the configurable area of the confirmation page. The content is contained in a rich text field that allows editing of text, configuration of that text, the insertion of merge tags, images, or attachments to the confirmation, as desired.
See Customizing the Confirmation Page for details on editing confirmation pages.