It is possible to install EZ Notes Search using the command line without being prompted during the installation. To do this you must open the CMD.exe window by using the "Run as administrator" item on the right mouse menu since you must have administrative privileges to install.
The command line for the 64 bit intaller is:
msiexec /i NotesDesktopSearchConnector-x64.msi /qn ALLUSERS=""
if you want to install for just the current user or
msiexec /i NotesDesktopSearchConnector-x64.msi /qn ALLUSERS=1
if you want to install for all users (note the 1 should not be quoted).
To uninstall from the command line:
msiexec /x NotesDesktopSearchConnector-x64.msi /qn