These screenshots were taken using Eudora 6.1. Eudora version 5.x has many problems with its SSL support, and it may not be possible to make it work. All versions of Eudora have strange behaviour with IMAP, so we recommend avoiding it if you value your sanity.

Under the “Tools” menu, choose “Options…” and “Checking Mail”. From the “Secure Sockets when Receiving” menu, choose either “Required, STARTTLS” or “Required, Alternate Port”.