I preferred SysInspire Lotus Notes to Outlook conversion as it is the only best solution according to me which not only created a backup of my emails but also the software enabled me to preview the email contents. If you also want to backup IBM notes emails then download the free version of the SysInspire You can save 25 emails from each folder. You can also go for the preview of the files just before the final conversion.
Read More:- https://www.sysinspire.com/nsf-to-pst-converter/