Actually Thunderbird 38 can not import Eudora.. A bug renders it inoperable as you have found. The current intention is to remove the functionality permanently while fixing Outlook import.

So you will need to install V31 to import your Eudora mail. As for the location of the import folder that is set by a windows registry key created by Eudora.

See https://bugzilla.mozilla.org/show_bug.cgi?id=917961#c13 for the details of the key.

jrbaumgardner said I have my Eudora Application Data Folder, named Eudora, stored on my desktop. When I attempt to import my Eudora mail files with Thunderbird, it crashes Thunderbird. After a bit of sleuthing, I find that TB cannot find the mail folders. Where does TB assume that these Eudora folders are stored? Thanks.

Thanks very much for your answer. Using TB v. 31 worked with no glitches whatever. It imported all my Eudora mailboxes with more that 15 years' worth of archived emails. Truly appreciate your help!