If you want to convert PST to MBOX, the best tool is to convert eSoftTools PST to MBOX Converter Software. It works well. To make this clear, it just takes a few more moves. The conversion files of ANSI, as well as UNICODE PST, are accepted. The platform supports both old and new Microsoft Outlook versions. The trial edition allows all customers to convert up to 25 e-mail objects free of charge by folder.
More information:- Convert PST to MBOX