I know nothing of scripting but could the problem be you are launching RoboHelp without specifying the full path to Rh9?
Normally RevoUninstaller is recommended for removing programs as it removes registry entries left by the apps own uninstaller. However the free version may not work if it cannot see the program in Programs and Features. The site does state though that Revo Uninstaller Pro has a very powerful feature called Forced Uninstall. Forced Uninstall is the best solution when you have to remove stubborn programs, partially installed programs, partially uninstalled programs, and programs not listed as installed at all!
Microsoft did have a tool that cleaned up when an uninstall had failed. This page looks close. http://support.microsoft.com/mats/program_install_and_uninstall
See www.grainge.org for RoboHelp and Authoring tips
Peter, as always, thanks for your helpful advice. I'll take a look at those uninstall links.
And yes, regarding the scripting opening up RH 7, I did find out if I included the entire pathway to RoboHtml.exe for RH 9 that it opened Rh 9. I have a diff problem related to that. My script is opening up a new RH instance, not using the current one I have open.