5 Simple Steps to Convert Thunderbird File.
Download and install Thunderbird converter tool
There is available two option to import the Thunderbird file.
If you want to import from MBOX then, you have to select the “Import from MBOX” and click on “Add files” button to import the MBOX files.
If you want to directly import from Thunderbird then you need to select the “Import from Thunderbird” and click on “Auto Locate Thunderbird Database”.
This tool provides you "Four conversion types" to export the Thunderbird file like MBOX to PST, EML, EMLX and MSG. Select conversion type as per your requirement.
Choose the destination path where you want to save the converted file and click on "Convert" button to complete the conversion process.