Changing your password from within Eudora. It also shows how to change your password. Every account must have a password. Passwords must be 6 to 16 characters.
Shorter passwords are too easy to break through brute force computation.
Limiting passwords to 16 characters makes them slightly more portable. We know of systems that do not support passwords longer than 16 characters. We would not be able to share longer passwords with these systems. Passwords cannot be entirely alphabetic. This prevents users from using easily guessed passwords like names of relatives or common words.