If you have been around the Exchange world for a while, you may be familiar with the MFCMAPI tool (http://mfcmapi.codeplex.com/), which provides a graphic interface into the innards of a message stored in Exchangeor in a PST. I often use MFCMAPI to pry apart a message to find out what’s inside and why it is or is not behaving a certain way.
If you need to troubleshoot documents stored in a Lotus Notes NSF file, there is a similar tool available: Notes Peek (https://www.ibm.com/developerworks/lotus/library/ls-NotesPeek/index.html). Like MFCMAPI, Notes Peek provides a graphic view into the guts of a Notes database and its constituent documents (e.g. e-mail messages, calendar items, journals).
Notes Peek does not use the Notes client to access the Notes data, but uses the Notes C API, so you do need to have the Notes client installed on the workstation where you want to install and run Notes Peek. Notes Peek follows the same ACLs that you generally expect with Notes documents, so you will need the right credentials to access the documents.
You can download Notes Peek from IBM at the following address: (https://www-304.ibm.com/support/docview.wss?q1=notespeek&dc=D400&uid=swg24005686) If you want to know more, there is an oldie-but-goodie posting about the many things you can do with this virtual Swiss Army Knife that MickMoignard wrote nine years ago, but it is still true today.