To export Outlook OST to PST, you can use eSoftTools OST to PST Converter Software for a quick and reliable solution. This tool allows users to convert OST files into PST format without any data loss, making them easily accessible in Outlook. It supports recovery of emails, contacts, calendars, and attachments, even from damaged OST files, while preserving the original folder structure. The software offers a simple interface, ensuring a smooth and hassle-free conversion process for all users.