You can use TBBackup to backup all your important Thunderbird data. All data that have been chosen for backup are collected together in a common backup file. All data in this file are compressed and stored in a ZIP file format. Instead of executing many different files, now there is only one space saving ZIP file to be executed for backup.
With the help of TBBackup you can protect and backup the following Thunderbird data: E-Mail folders; E-Mail- and News-Accounts (POP3, IMAP, NNTP, RSS); Virtual folders; and Signatures.