If you can’t see default Silverlight control in Toolbox, run “devenv /setup” or “/reestsettings” in Run or “Visual Studio 2008 Command Prompt”

You may experience this problem when you try to run an existing SilverLight project.

I only know the quick and dirty solution to this problem. (at least, it worked for my app)
You’ll have to open the .xap file with an archive program like winara. Edit the AppManifest.xaml file, and change the version number into the current number (something like 2.0.30825.0). And your program should work.

I started to play with the SL3 with wcf, but keep getting the error when using default clientconfig file

Could not find default endpoint element that references contract ‘ProjectName.ServiceReference1.IService1′ in the ServiceModel client configuration section. This might be because no configuration file was found for your application, or because no endpoint element matching this contract could be found in the client element.

If you look at the config file you’ll see contract=”ServiceReference1.IService1″. This needs to be a fully qualified namespace, and should be changed to contract=”ProjectName.ServiceReference1.IService1″ (or whatever namespace is specified in your Reference.cs file)

Silverlight does not have the Page type, the term is currently used is RootVisual UserControl. RootVisual object is analogous to the root window in WPF and can only be set once for the lifetime of the app, and is effective once the Application’s Startup event is raised. But this not true, you can set RootVisual as many times you want. So Application_Startup can be used to call multiple Silverlight controls.

    <form id="form1" runat="server" style="height:100%;">
        <asp:ScriptManager ID="ScriptManager1" runat="server"></asp:ScriptManager>
        <div  style="height:100%;">
            <asp:Silverlight ID="Xaml1" runat="server" InitParameters="ControlId=Page" Source="~/ClientBin/SilverlightApplication1.xap" MinimumVersion="2.0.30523" Width="100%" Height="100%" />
        </div>
    </form>

		<object data="data:application/x-silverlight," type="application/x-silverlight-2-b2" width="100%" height="100%">
			<param name="source" value="ClientBin/SilverlightApplication1.xap"/>
			<param name="onerror" value="onSilverlightError" />
			<param name="background" value="white" />
			<param name="initParams" value="ControlId=BookStore" />

			<a href="http://go.microsoft.com/fwlink/?LinkID=115261" style="text-decoration: none;">
     			<img src="http://go.microsoft.com/fwlink/?LinkId=108181" alt="Get Microsoft Silverlight" style="border-style: none"/>
			</a>
		</object>

and in the App.xaml.cs

        private void Application_Startup(object sender, StartupEventArgs e)
        {
            if (e.InitParams.ContainsKey("ControlId"))
            {
                switch (e.InitParams["ControlId"])
                {
                    case "BookStore":
                        this.RootVisual = new BookStoreWithConverters();
                        break;

                    case "Page":
                        this.RootVisual = new Page();
                        break;
                }
            }
        }

Today I have found very good tutorials for Expression Blend from www.movielibrary.lynda.com. These tutorials covers the topics like
Overview and Installation, The Workspace, Managing Your Projects, Drawing in Blend, Appearance, Working with Text, Using 3D, Media Integration, Layout Controls, Media Integration, Layout Controls, Transformations, Animation and Interactivity, WPF Controls, Working with Data, Application Deployment, Please find following Expression Blend tutorial pages
Expression Blend
Getting Started with Expression Blend 3.75 hours

Expression Blend Beta Preview 2.5 hours

Expression Design
Getting Started with Expression Design

Hope these tutorials are useful. Suggest the some more best tutorials on this topic in bellow comment section.

Silverlight 2 Beta2 was released today.  You can download both Silverlight 2 Beta2 and the Visual Studio and Expression Blend tools support to target it here.

Beta2 adds a lot of new features (more details below), but is still a 4.6 MB download that takes less than 10 seconds to install on a machine.  It does not require the .NET Framework or any other software to be installed for it to work, and all features work cross-browser on both Mac and Windows machines.  These features will also be supported on Linux via the Moonlight 2 release.

Silverlight 2 Beta2 supports a go-live license that allows you to start using and deploying Silverlight 2 for commercial applications. There will be some API changes between Beta2 and the final release, so you should expect that applications you write with Beta2 will need to make some updates when the final release comes out.  But we think that these changes will be straight-forward and relatively easy, and that you can begin planning and starting commercial projects now.

You can build Silverlight Beta2 applications using the VS 2008 Tools for Silverlight and Expression Blend 2.5 June Preview downloads.  You can download both of them here.  The VS 2008 Tools for Silverlight download works with both VS 2008 and the recent VS 2008 SP1 beta release.

Problem ~

An Error Has Occurred:
Silverlight Tools cannot be installed because one or more of the following conditions is true:

1. Visual Studio 2008 RTM is not installed.
2. The Web Authoring feature of Visual Studio is not installed.
3. A previous version of the Silverlight Runtime is installed.
4. A previous version of the Silverlight SDK is installed.
5. The Visual Studio Update KB949325 is installed.
6. A previous version of Silverlight Tools is installed.

To continue, please install or uninstall the appropriate products and run this installer again.

Solution ~

Short Answer: You are sure that all of conditions above are false but you are getting this error. Then, The shortest answer is “uninstall Silverlight 2 beta1 SDK” from your machine.

That’s all. You should be able to install after uninstalling. but If you want to read more details, please keep on reading further.

Detailed ~

Step #1. Install Visual Studio 2008 release version or RTM version

You have to install the release or RTM version of Visual Studio 2008 in your machine. Your Visual Studio should be Professional Edition or Standard Edition or Team System. You can’t use VS 2008 beta or Express version.

Step #2. Install the Web Authoring Component of Visual Studio

You need to check whether you have Microsoft Visual Studio Web Authoring Component installed in your machine or not. If you have installed Visual Studio 2008, you already have that web authoring component installed. but just in case you accidentally remove that component, you can run WebToolsCore.exe to install that component manually. The setup fiel is located under WCU\WebToolsCore of VS DVD. If you are not sure about what VS Web Authoring Component is, you can read this post.

Step #3. Remove the Visual Studio Update KB949325 if it’s installed

You have to remove that Visual Studio Update (KB949325) from your machine.

If you are a Windows Vista user, please go to “Control Panel” and open “Programs and Features”. Then, Click “View installed updates” and find “KB949325″.

If you are XP users, go to “Add and Remove Programs” and select “Show Update”. And find “KB949325″ in the list.

Step #4. Uninstall all of the previous versions of the Silverlight Runtime/SDK/Tool

You have to uninstall all of the previous versions of Silverlight runtime/SDK/Tool from your system.

Uninstalling is very simply. but sometimes, you might face some weird problems. One of my friends faced one weird problem when he tried to uninstall the previous version of Silverlight. He installed “Silverlight 1.0 SDK VS 2005 template” in his machine long time back. The time when he installed that SDK, he had VS 2005.

but after sometime, he removed VS 2005 from his machine. Now, he wanted to remove SL 1.0 SDK but he couldn’t. The message below kept on showing when he tried to uninstall.

So, I suggested him to use Windows Installer CleanUp Utility to remove that SDK and he did it.

Note: I would like to suggest you to use CCleaner to scan your registry and fix all issues after removing SL 1.0 SDK from your machine.

Step #5. Uninstall Silverlight 2 (beta1) runtime, SDK, Tool for Visual Studio 2008

Please uninstall Silverlight 2 (beta1) runtime, SDK, Tool for Visual Studio 2008 in case you have installed before facing this problem.

Step #6. Install Silverlight 2 (beta1) runtime

Now, you can install Silverlight 2 (beta1) runtime. (It’s just for the sequence of installing. That’s why I asked you to uninstall SL2-related things first.)

Step #7. Install VS 2008 Web Development Hot-Fix

You can download this hot-fix from this link. then, install it in your machine after installing Silverlight 2 runtime.

Finally,

Now, you can run silverlight_chainer.exe again.I hope you should be able to run the setup successfully. Feel free to let me know if you have any problem in installing SL 2 Tool.

Issues after installing Silverlight 2 Tool for VS 2008

#1: ‘Microsoft.VisualStudio.Web.Silverlight.IVsSilverlightService’ error

If you are getting one of the following error, you have by-passed the validation of Silverlight 2 Tool installer by extracting (winrar-ing) the silverlight_chainer.exe or following this post. You have to follow 7 steps that I mentioned above to install Silverlight 2 Tool firstly. If you are able to install that tool, the following error will be disappeared.

OR

#2. The project type is not supported by this installation

Run devenv.exe /resetskippkgs in case you got this error. (Thanks to BradleyB for this post.)

Silverlight Blueprint for SharePoint site: http://www.ssblueprints.net/sharepoint/ !

 You can read more details on Patrick’s blog and Karine’s blog (she posted some screenshots). The Blueprint will also be announced by Bill Gates during the SharePoint Conference keynote later today, the SharePoint team blogged about the other announcements as well (SharePoint Online and Microsoft Search Server 2008 Epxress).