Many people have reported getting "Windows Installer Not Responding" errors when trying to install a wide variety of programs. The bug (and the initial fixes) was reported here, among many places. Then a few hours later, Chris Holmes (who found the original bug) made this second discovery; Microsoft has now acknowledged the problem and provided the solution through the Action Center. Follow the directions on the screenshot or go via regedit and delete the key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\SQMClient\Windows\DisabledSessions. Posts on TechNet and other reliable forums all report of success installing everything from Adobe, Java and even games that had failed to load previously.