For the gateway to talk with Domino, there must be a Notes client already installed on the gateway machine
Add the following string values to HKEY_LOCAL_MACHINE\SOFTWARE\Waveset\Lighthouse\Gateway in the Windows registry to ensure Domino works properly:
notesInstallDir. This is the location where the client is installed and where the notes.dll file is location. Typically, the location is something like C:\Lotus\Notes\.
notesIniFile. The full path to the Lotus Notes initialization file, including the file name. You should copy the file from its default location (such as C:\Lotus\Notes\notes.ini) to the directory containing the Identity Manager gateway. Therefore, you should set the value of this registry key to a value similar to C:\GatewayDir\notes.ini.
Make sure the Notes client is running with a network-enabled profile. If you change the network connection after you copy the ini file, you must re-copy it or run the client through the command line, as in: