I've set up a new pc, installed Thunderbird and copied the contents of my old profile into the new profile. Everything works fine when I first start TB, but the next time I start I have a blank(ish) screen - the menus are there, the template is there and the 'windows' are showing, but are all blank (i.e. no folders, no emails, no accounts). If I then re-start in safe mode one of my accounts is missing (an exchange server via Owl). Presumably this is because the owl addon is disabled? When I then try and open TB after I've started in safe mode, the whole program won't load. (but will re-load in safe mode). If I re-copy the profile across, the whole cycle starts again. If I re-copy and open into the working version, then disable all add-ons, it doesn't improve (will only open in safe mode). I have also tried renaming the profile that TB created on the PC to match the name of the profile I'm copying the contents of, incase there was an internal link, and changed the profile JSON file to refer to this, but that didn't help. I can just re-do the accounts and reinstall the add-ons, but I've got a lot of useful things set up, like quick folders, filtering rules, quick text that are with these add ons that I'd rather not have to start again with. Any help is appreciated.