Lotus Notes archive files can’t be opened directly in Outlook since Outlook doesn’t support NSF files. A manual method involves restoring the archive in IBM Notes, exporting emails to CSV, and then importing them into Outlook. However, this process can be time-consuming and may result in data loss or missing attachments. A better solution is eSoftTools NSF to PST Converter, which directly converts NSF archive files to PST without IBM Notes. It keeps the original email structure, attachments, and formatting intact. The software also offers a preview option, allowing users to check their NSF files before conversion.