You can't open an NSF file directly in Outlook 2013, 2016, or 2019 since Outlook doesn't support the NSF format. The best way to handle this is to first Export Lotus Notes email to PST. The TrustVare NSF to PST Converter makes it easy to do this without having to go through a lot of procedures. The application converts Lotus Notes NSF files into PST files that Outlook can readily read. It protects emails, attachments, contacts, and the structure of folders while it works. The tool works with multiple versions of Lotus Notes and Outlook, which makes it a good choice for a lot of people. It also has a free demo version that lets people try out the conversion process and see the results before they buy the full version.