For several years, I have been using three accounts in Thunderbird. Suddenly, on one account, all emails and sub folders have disappeared. None of the folders show, (Drafts, Trash, etc) except for "Inbox", and clicking on this has no effect, although it does appear that there are "placeholders" but no data for the emails that should be in the inbox. The folder for this account in Profiles\xxx.default\mail is empty. The folders for the other accounts have the appropriate files and sub-folders. I cannot find the missing .sbd folders or .msf files in the Recycle folder or anywhere else on the hard derive. I have tried "Repair Folder" with no effect. There is a possibility that Thunderbird may have been in the process of Compacting Folders when I shut the computer down. Any suggestions for recovering these files/emails would be greatly appreciated! Thunderbird 38.5.1, Win XP SP3