Locate and remove Lotus Notes by deleting the related files, recommended a trained software professional would better do this job
Eliminate the registry entries if you can and delete connected directions.
Search in Internet, can find out what files and registry entries need to be deleted. But this removal is only recommended for experts, for deleting the wrong file or registry key may render Windows unbootable.
Or this might be prevent the Notes installer from detecting any previous versions if you installed earlier.
Remove the registry key HKEY_CURRENT_USER\Software\Lotus\Notes\Installer (and all the subkeys).
Remove the registry key HKEY_LOCAL_MACHINE\Software\Lotus\Notes (and all the subkeys). Now depending on if the Windows Installer service still has info about the Notes install, then you may be done. Also look for log.nsf file! Look here for IBM’s way.