Hey there, this problem now occurred twice to me in January and it really gets on my nerves as I have to be very careful in securing my e-mails all the time. This is what happens: I open Thunderbird as usual. And then all of the sudden all the folders I created to sort out the e-mails in my inbox are gone. And the e-mails in there as well. I use Imap if that helps. I could restore most of the e-mails because these folders exist on my server too and I didn't delete them there. However what happens is really annoying. I downloaded a program to look for the lost e-mails and this told me that they have been overwritten with other documents on my computer but I didn't do anything at all! What could I possibly do besides changing to another E-mail client to solve this problem? Kind regards, Linda