The demo version of Softaken OST File Exporter will convert only 10 items from each Folder. Trial Version of this software is free of cost to check software features and function. If user want to convert unlimited numbers of OST files into PST, EML, MSG, MBOX etc. formats than purchase license version of Softaken OST File Exporter Software.
Try the Demo Version of the software from Softaken Official site: https://www.softaken.com/ost-to-pst-converter