old style toc and Odyssus

I stupidly installed Leopard in Jan,lost 9 years of maul,reinstalled
eudora (used since 96_)discovered the fault was not mine ..turned off
sound and have been struggling ever since. This week all the mail in
my out box was marked unsent (not a problem )but all the messages and
addresses were gone. I run a national Breed Rescue for dogs and I
need accurate sent messages.
Will changing the toc file possibly prevent this...It seems to happen
at night when the program is closed.
I use 25 filtered mailbixes and 15 folders....I tried Mosellas
Thunderbird but it would not impirt the mail
and I did not like it. I am legally blind so I need something as close
to Eudora as possible and found the short description of Odyssus and
liked the sound. Is there another list I should be on to learn more
and what are your thoughts about it.
I wa,t Eudira but what choice do I have :-(
Petie