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If the Thunderbird program was uninstalled, you may still have some remnant files that contain your Inbox database, or your Contacts data, etc. You would look for them in a certain place in whatever version of Windows you now have (let me know, so that I may be more specific), copy them to an entirely different directory for the interim, then reinstall Thunderbird, then either Import the email database or Contact file, or else simply copy them into the version of Thunderbird you would then have installed (and, I would have to know what version, in order to advice you more exactly.)
That would probably work, if no other factors (such as total erasure of database / Inbox / Contacts files) intervene.