Eudora /juːˈdɔːrə/ is an email client that was used on the classic Mac OS, Mac OS X, and Microsoft Windows operating systems. ... In 2018, after being years out of print, the software was open-sourced by the Computer History Museum.
https://en.wikipedia.org/wiki/Eudora_(email_client)
When your software is in the Computer History Museum, it might be time to move on.
That's kinda why I posted this.