Convert PST to MBOX and Import Outlook to thunderbird
Try this Regain PST to MBOX Converter tool and convert your PST file into MBOX file in just easy process. This tool can store the MBOX file after performing conversion at any desired location in this system. It is the best option for you as it is very user friendly and flexible. This tool Instantly Convert PST file to MBOX format. this tool Support 20+ Email Clients and also Converts Encrypted PST files into MBOX file.
Includes Advance Data Filter option:-
After clicking MBOX as an option to save file, the tool displays another window with various features. Another option is “Apply Data Filter” Apply the date range and you can conduct selective conversion of Outlook into MBOX.
You can download this software free demo version from here: http://www.psttomboxconverter.emltopstutility.com/