The Aryson OST to PST Converter Tool is a highly regarded solution for converting large OST files into PST format efficiently. It includes features such as duplicate removal, date range filters, and the ability to back up OST files without attachments.

Steps to Backup OST Files to PST:
1. Install and launch the OST to PST Converter with administrative rights.
2. Click the "Select Files" button to add your OST files, then press "Next."
3. Select the desired files or folders from the tree structure and preview them in the Advanced Preview Panel.
4. Choose your preferred file format or email client.
5. Select any additional features or filters.
6. Finally, click the "Convert" button to start the backup process.
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