My iMac is fried, unrecoverable... but I was able to save the whole Thunderbird folder containing Crash Reports, installs.ini, Pending Pings, Profiles and profiles.ini which I believe is everything, all my emails and accounts etc. I have transferred the data to a Mac Pro running Mojave on a spare drive. I have installed a Thunderbird on my Mac Pro. I have tried numerous fixes but I couldn't get Thunderbird to see my emails, and it would start with Welcome and Set Up Existing Email Address which isn't what I want, but having tried a few ways I have become unsuccessfully familiar. I have tried http://kb.mozillazine.org/Moving_your_profile_folder_-_Thunderbird "Nothing you do works" (but I think it was referring to Windows so that's not good ;) by completely deleting the profiles.ini file, starting Thunderbird and thus creating a new profile, copying the "contents" of my of my Profiles/ui1yf25m.default folder and replacing the data over the top of the newly created Profile (which has nothing of worth in it) but it keeps the newly created working Profile folder intact thus Thunderbird should see the data and load all my emails and accounts - but it didn't. The newly created profiles.ini file had 0dcrwgtx.default (which I moved all my files into) plus it had izoic061.default-release (so 2 profiles stumped me). Wiling to try anything :) John