Download and use eSoftTools PST to MBOX Converter software to import outlook mail folders from PST to MBOX files. It will convert PST to MBOX files with complete emails and attachments. There is no restriction on the number of files for conversion. With the software user can convert single as well as multiple PST files without any extra efforts. Download its demo edition and get the ability to export PST file to Thunderbird MBOX with upto 25 emails for free.
Read More:- Export PST file to Thunderbird
