I am using System.Diagnostics.Process.Start
from a desktop application to start the default browser to visit a link, as below. This is using C# with .NET 4.0 o
For WinRT apps only, it's simply
Launcher.LaunchUriAsync(new Uri("http://www.google.com"));
Take a look here.
It seems that you need to specify the process name under Win8. The answer below comes from Armin's answer here.
var startInfo = new ProcessStartInfo("explorer.exe", @"http://www.google.com");
Process.Start(startInfo);