Have 4 different e-mail accounts in my TB; problem is only with the account at top of listing; Incoming mails show in inbox; when select any of the new mails (goes from bold to regular print) it does not show anything in the content pane; if I shut down Thunderbird and reopen the problem is temporarily fixed (just for that opening)..next time I got to TB the problem reoccurs with just that "top"account (others all work just fine). Have checked everything I know, but this 81 year old, non-techie is baffled. What can do to fix?