Simply use OST to PST Converter Tool. This tool is a secured software through which you can convert OST files to PST file format. This tool helps to do conversion tasks without any hassle. This tool generates the preview of every email of OST files. Comes with an open or preview option. You can view these OST files before converting them to other formats. Users can also save OST files in MSG, EML, and HTML format. The demo version of this software exports the first 50 items per folder freely.