It depends on what was done. Thunderbird does not maintain backups. If a POP account or Local Folders were deleted or tampered with, there may be no recovery. If a new profile was created, you might see if there is a prior folder in the ...appdata\roaming\thundrbird\profiles folder.

Thanks a lot David. I successfully reached the appdata/roaming/thunderbird/profiles and got the followings :

- j7wxxxxx.default-release date modified 6/28/2024 - u29xxxxx.default date modified 1/16/2024

Can you help to understand this? And what shall I do afterwards.

Thanks a lot, Bambang

These are two profiles. Check in each one and click the Mail folder to see if a POP account is there If it is, click the account folder and see if there are any message files, such as inbox, sent, etc. there may be other entries such as inbox.msf, sent.msf, etc. Those would be messages - the msf files are just indexes and would be rebuilt if needed. Check also the Mail\Local Folders folder for any local message files. If found the files can be copied to the Mail\Local Folders folder of the active profile - which is probably the one with the newest date.