Link to download the Lotus Notes C++ Toolkit
I've received a few questions about where to get the lcppn30.dll file that is required by SharePoint to connect to Lotus Notes. Here's the link for reference: https://www14.software.ibm.com/webapp/iwm/web/reg/download.do?source=ESD-SUPPORT&S_PKG=CR3DNNA&S_TACT=104CBW71&lang=en_US&cp=UTF-8
You will have to register with IBM to download the file.
The version that contains the file is Lotus C++ API Toolkit Release 3.0 for Windows English US.