title: Getting blank InstallDate for few installed softwares, even if date is there in registry
body: <p>I am using below code to get list of installed software, i am able to get installation date for around 90% software but for around 10% software, i am getting blank in installation date <strong>(even though the installdate is present in their registry key)</strong></p>
  
  <pre><code>key = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall");
      foreach (String keyName in key.GetSubKeyNames())
      {
         RegistryKey subkey = key.OpenSubKey(keyName);
         string appname = subkey.GetValue("DisplayName") as string;
         string Vendor_Publisher = Convert.ToString(subkey.GetValue("Publisher"));
         string Version = Convert.ToString(subkey.GetValue("DisplayVersion"));
         string InstallDate = Convert.ToString(subkey.GetValue("InstallDate"));
      }
  </code></pre>
  
  <p>The application is installed on windows 7 (32-bit)
  <img src="https://i.stack.imgur.com/J7rzF.png" alt="InstallDate"></p>