Eudora

Eudora was a popular mail program in the 1990s.

Eudora uses the mbox format to store messages (an entire mailbox/folder in one file, with a .mbx extension), dealing with the infamous "From" line parsing problem by using a binary file known as a Table of Contents to index the offsets of each message in the mailbox file.

Format information

 * Eudora .toc File Structure and Utilities

Metaformat files

 * Synalysis grammar file (for Hexinator / Synalize It!; more details)

Software

 * Classic Eudora (Internet Archive)
 * Eudora OSE (Open Source Edition)

Other links

 * Wikipedia article
 * Really Old Eudora Email, Preservation, Parsing Woes, and Hidden Bits