I have 10 email addresses that I download email for. I had email going 5 years back. This morning 3 of the inboxes have no body text for any of the emails.

Here's the place to start looking: http://kb.mozillazine.org/Thunderbird_:_Issues_:_Disappearing_mail If you have email going back five years in your ''Inbox'', then I'd advise moving it asap into other folders. Thunderbird runs best when you keep the Inbox down to just a few messages: http://kb.mozillazine.org/Keep_it_working_%28Thunderbird%29