Install protocol handlers (Office SharePoint Server 2007) and configure to crawl Lotus Notes
In this article: https://technet2.microsoft.com/Office/en-us/library/9e71760e-5459-48dd-9332-d80e6018b1261033.mspx?mfr=true
• Configure Office SharePoint Search to crawl Lotus Notes
• Prepare the index server to crawl Lotus Notes
All crawled content requires the use of a protocol handler to gain access to that content. Microsoft Office SharePoint Server 2007 provides protocol handlers for all common Internet protocols, such as HTTP, HTTPS, and FTP. However, if you want to crawl content that requires a protocol handler that is not installed with Office SharePoint Server 2007, you must install the third-party or custom protocol handler before you can crawl that content.
The protocols supported by the default protocol handlers are: bdc, bdc2, file, http, https, rb, rbs, sps, sps3, sps3s, spsimport, spss, sts, sts2, sts2s, sts3, and sts3s.