Sponsored mode provides the full-featured Eudora desktop e-mail program at no charge, and it includes free technical support (up to six calls per year). The software displays a series of static on-screen advertisements that do not interfere with the user's e-mail workspace. The advertising does not appear within the body of e-mail messages.
Paid mode provides a registration code that can be used to activate the full-featured version of the software without advertising.
The Light mode is a free download of Eudora that automatically installs in the Sponsored mode, but users have the choice of switching to Light mode if they prefer.