How to Convert Multiple EML Files into a Single PST? If you have many EML files and want to combine them into one Outlook PST file, you can use eSoftTools EML Converter Software. This tool allows users to load multiple EML files at once, preview their content, and convert them into a single PST file with complete email data and attachments. It helps maintain the original folder structure and email formatting, making the migration process simple, organized, and reliable for accessing emails in Microsoft Outlook.