You can use Convertertool’s OST to PST Converter Tool, which provides a comprehensive solution for converting OST files to PST format. This tool not only simplifies the conversion process but also supports converting OST files to MBOX and various other file formats and email providers in just a few steps. It allows users to migrate from Outlook to platforms like Gmail, Thunderbird, AOL, IMAP, Zoho, and more. The application is highly recommended for exporting OST files to multiple formats while maintaining the folder hierarchy. It also offers the option to convert email attachments to PDF format. The software is compatible with all Windows OS versions, including Windows 11, and comes with a free demo version and technical support.