If you are troubled with your corrupt, damaged Outlook files and wanted to switch from Outlook to Lotus Notes then I will say, the best option for migrating email files is using a free tool or else you can go for manual process too. But to be risk-free never forget to take backup of the files.
If you are facing a problem of OST corruption issue and you don’t have any idea how to recover it then here is the solution, the users can take the benefit of InQuit OST Recovery tool which not only recovers the deleted files but also allows the users to save the files into cloud base important application Live Exchange Server and Office 365. Read More: InQuit OST to PST converter
This is a free utility to convert Outlook PST data to NSF file format, It is a part on Lotus Notes migration tools, you can find it in the directory of Notes clients program. By the using of this utility you can manually convert PST file to NSF file format. If you want to use a third party utility then try outlook to notes converter which is a secure and easy way to perform this task.
More Info :- Outlook to Lotus Notes Converter