C#

RegistryKey rk = Registry.LocalMachine;
                RegistryKey rkprograms = rk.OpenSubKey(@"Software\Microsoft\Windows\CurrentVersion\Uninstall");
                foreach (string s in rkprograms.GetSubKeyNames())
                {
                    int idx;
                    idx = s.IndexOf(".NET");// see if anything with .NET in the name is installed e.g. Microsoft .NET Framework
                    Console.WriteLine(idx);
                    {
                        Console.WriteLine(s);
                    }
                    Console.ReadKey(true);
                }

RegistryKey RegKeyIN = Registry.LocalMachine;
                RegKeyIN = RegKeyIN.OpenSubKey("SOFTWARE\\MICROSOFT\\WINDOWS NT\\CURRENTVERSION");
                Object Date = RegKeyIN.GetValue("InstallDate");