A lot of people using win7 have been clicking the "Turn Windows Features on or off" link in their settings and finding an empty dialog window. I know because I did a search when it happened to me. Most of the suggested solutions seem to be to run an automated repair program. However, since I only installed my OS a few hours ago I had a good idea of how I broke the system.
Open administrative tools and make sure the "Windows Modules Installer" service is running. If you went on a spree disabling services that looked unnecessary it could be what is causing a blank list for windows features.
Open administrative tools and make sure the "Windows Modules Installer" service is running. If you went on a spree disabling services that looked unnecessary it could be what is causing a blank list for windows features.