I am distressed. I've used Thunderbird for years and had to create a new version of my IMAP account using EXCHANGE. I did that. I know it was successful because the EXCHANGE account showed up in Thunderbird and I then spent days transferring emails from the old IMAP account personal email folders into duplicate folders in the new EXCHANGE account. Then today I closed my browser. When I re-opened Thunderbird, the new EXCHANGE account was absent. Since I can't use the old IMAP account any more, I tried again to create an EXCHANGE account. When I tried to do that, I got a message that "the server already exists" (see image below) and I am unable to complete the task. So the previously created EXCHANGE account has disappeared, with all my emails in it, I can't create a new one, and the IMAP no longer works (and won't accept my password to send or receive). I feel completely stuck and I've lost several years of emails. The fact that the message said that the server already exists makes me think and hope that my EXCHANGE account still exists somewhere. Can you help me find it? Many thanks in advance. Steve