To efficiently merge multiple EML files in PST format, you can use the EML to PST Converter. This tool allows you to efficiently merge multiple EML files into a single PST file without converting the data. It also saves email attachments during conversions. The software allows users to browse EML files in Outlook and convert them to PST format from any email client that supports EML. Additionally, users can edit their EML files based on criteria such as file size and name. The tool automatically opens a generated PST file for easy access. It is compatible with all Windows OS versions including Windows 10, 8.1, 8, and 7.