I have several accounts in Thunderbird - all but one are working fine. I have 2 Outlook accounts and 1 has suddenly stopped working. All the file folders under the account name disappeared. When I restarted my computer, an "in box" reappeared but no other folders and the inbox was completely empty. I can still access this Outlook account on line however. I have searched the web for advice and tried all the basic fixes including updating to latest Thunderbird version but still cannot access the account.