These How-To tips are taken from The Tutor.com Classroom: Architecture and techniques using Silverlight, WPF, and the Microsoft .NET Framework.Use the isInstalled() function provided by Silverlight.js:
You can check out the Silverlight Tutor.com Classroom in "practice" mode, although the real experience is with a live tutor on the other side!
Silverlight.InstallAndCreateSilverlight = function(version)
var retryTimeout = 1000; //the interval at which instantiation is attempted(ms)
else if (!Silverlight.isInstalled(version))
TimeoutDelegate = function()