Well, it is a little more complicated.
I have installed my CS3 on 2 systems - Home and the one I use for presentations, etc.
Everything works fine on the Home system - an original install of CS3.
My portable one (where I originally installed and then let expire and uninstall the trial version of CS2) WILL NOT WORK with Droplets.
I have found references to the problem on ther Adobe forum and surprise surprise it is a known problem that Adobe ahas apparently ignored. I tried Adobe Technical support and gave up after 30 minutes. I Tried doing a repair. Next is to uninstall, reinstall and then see what happens.