I'm here just to solve How to Convert PST Files to Thunderbird? that software name is eSoftTools PST to MBOX Converter Software. It can convert Outlook PST files to MBOX files with ease. Before converting PST files to MBOX files, it displays a live preview, with a date filter option available to all users during this procedure. If someone wants to change a specific date, they are free to do so. This software can be used by both technical and non-technical people. All customers have access to the demo version.