Not so much a question as an answer, but I don't have the time to get organised as a contributor. Every so often I get an email which presents as html code instead of the correct email, and I know from experience that the fix for a corrupted folder can take a long time to fully reload. The following fix for an INDIVIDUAL email works on Microsoft servers (outlook, hotmail, msn etc): 1 - note the date and time of the corrupted email 2 - using a browser log directly into your email service 3 - create folder, you could call it "repair" (if you haven't already done so) 4 - find the email in the inbox (the date and time will help) 5 - assuming the email on the server is OK, right-click and move it to the repair folder 6 - go back to Thunderbird, you should now have a repair folder containing the (hopefully uncorrupted) email (you might have to wait for it) 7 - right-click the email and move it to the inbox - it should replace the corrupted email.