Thank you for letting me use TBP.
I was using ThunderBird Portable (TBP) w/ no problem until 29th May in San Francisco. However, when I went back to Lyon, France and ran TBP, I lost almost all of the folders, sub-folders and emails I'd kept for ages.
My TBP is stored on a USB key (Patriot Slate 125GB), and run under Windows 10 on Thoshiba dynabook R73/38MW. I'm downloading my emails from Gmail server.
Come to think of it, exactly the same problem happened before when I returned from San Francisco to France two years ago.
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