Thunderbird is suddenly opening without any of my emails or folders, and asking me to set up an email account - so I put in my email details (I'm with aol) - and it connects to the aol server and my folders re-appear (initially without emails in them, but when I click on the folders the emails start downloading afresh from aol). So it seems that all will be well when the emails are all downloaded again. HOWEVER, after closing Thunderbird and opening it again, all my emails are gone again, and Thunderbird is yet again asking me to set up an account. I can do this again, and the same thing will happen again. Everything is lost again when Thunderbird is closed, and when I start it again, I will be asked to set up an account, and all my emails are gone yet again. I have been using Thunderbird for years and years and years. Suddenly out of the blue this happens, and I'm stuck with using aol's web mail platform directly (not great!!!) Also, Thunderbird suddenly looks different - like it's been updated (which I assumed initially had happened) but the update history still only shows the final release for Windows 7, so this is a bit puzzling, and an odd coincidence that the layout and appearance of Thunderbird has changed at the very same time it stops working for me.