Search not working in Thunderbird

Problem

You are trying to use the search function in Thunderbird, but it doesn't do anything.

Cause

This is probably due to crash in Thunderbird and it may have corrupted the search database.

Solution

Rebuild Thunderbird's Search Database by following the instructions provided in:

https://support.mozilla.org/en-US/kb/rebuilding-global-database

This process will take some time, so the Search function will not be 100% usable as it is rebuilding the database.  Please give it half an hour to an hour, depending on how big your mailbox is, to rebuild the search function.