During streamer installation, can't finish - config flashes and disappears

Windows 7 Pro x64, no other Splashtop programs installed.

During installation, when it usually shows the configuration screen where I put in the deployment code, I see the config screen and toolbar icon - the config screen flashes just for a moment and after a couple seconds the toolbar icon disappears as well.

Have uninstalled and reinstalled several times, including with anti virus disabled.  No other computers in this office that are configured identically have had any problems.

Terminal Services isn't showing in the Services list, so isn't disabled