Web Platform Installer says asp.net is already installed (its not)

Just trying to download it from http://www.asp.net/downloads for the first time. Web Platform Installer says regarding "Frameworks and Runtimes" (and also "Visual Studio Tools"), "All the recommended products from this group are already installed", even though they're not. Did have something called Visual Studio Runtime Redistributable installed which is just a handful of DLL's. I uninstalled it though - made no difference. Also removed entries from registry with "Vi开发者_StackOverflow社区sual Studio" in them, also made no difference.

Service Pack 3 had to be installed.