If StartMenuInternet is not set, where else can I look for the default browser?

Question

key = Registry.CurrentUser.OpenSubKey(@"Software\Clients\StartMenuInternet", false);
if (key == null)
{
    key = Registry.LocalMachine.OpenSubKey(@"Software\Clients\StartMenuInternet", false);
}

On a very few machines this is coming up blank. When regedit is probed, the key is found to be (value not found). What are my options?

Answer 1

I needed

if (key == null || key.ValueCount == 0)
                {
                    key = Registry.LocalMachine.OpenSubKey(@"Software\Clients\StartMenuInternet", false);
                }