Who is your email provider?

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Dear Zenos, These two folders disappeared after "hard - by button" restarting the laptop due to unresponding. All (programs, files) except these two folders in TB is correct. Please find attached file with these information. Looking forward to hearing from you gucio

I think (and hope!) that Thunderbird has forgotten where your messages are stored. Did it at any time ask you to set up your accounts again? Are you using any anti-virus or anti-spam software that might have quarantined your files?

I'd look at the profile. You may find it has generated new messages stores and the old ones are still there. If so, we can re-connect them to Thunderbird, or import them.

In your profile folder, we need to look for a Mail subfolder, and hopefully, three folders inside which will have names based on your three servers (interia.pl, poczta.pl and wum.edu.pl).

https://support.mozilla.org/en-US/kb/profiles-where-thunderbird-stores-user-data