I don't understand what 'from my previous session' means. Please provide more details about

• what exactly you're doing
• what happens
• what you expect to happen

WynandKok said

For years I have been using Thunderbird for my e-mail. I opened an additional mail account recently. Since then, every time that I open Thunderbird, all e-mails from my previous session would be gone

Hi, Thanks for responding. When opening Thunderbird my e-mails download as normal. At the end of the day, I close Thunderbird and shut down my PC. When I turn on next day and open Thunderbird my inbox is empty, with all my e-mails from the past gone. I expect all my old e- mails to be in my inbox until I delete them. It seems as if all my old e-mails are deleted from my inbox every time I close Thunderbird. Luckily I have copies of everything on another PC, but I need Thunderbird to keep all my old e-mails on this PC until I decide to delete them.

See if this article helps. http://kb.mozillazine.org/Disappearing_mail

I have this problem to. I had 20 e mails on my computer, (Windows 10 64 bit) one day and the next day when I started my computer they were gone. http://kb.mozillazine.org/Disappearing_mail didn't help. Its for a different version of my thunderbird