//Determine if Silverlight is installed....
function isSilverlightInstalled() {
    var browser = navigator.appName;
    var silverlightInstalled = false;
    if (browser == 'Microsoft Internet Explorer') {
        try {
            var slControl = new ActiveXObject('AgControl.AgControl');
            silverlightInstalled = true;
        }
        catch (e) {
            silverlightInstalled = false; 
        }
    }
    else {
        try {
            if (navigator.plugins["Silverlight Plug-In"]) {
                silverlightInstalled = true;
            }
        }
        catch (e) {
            silverlightInstalled = false;
        }
    }
    return silverlightInstalled;
}