Hello Ben,

There was an update of the controls that resolves the design-time issues with Blend. Please download the controls again.

I am sorry for any inconvenience caused.

Regards,
Miroslav
the Telerik team

Ben, Miroslav

I had this same problem yesterday. What I found was that in VS I had Telerik.Windows.Controls.Navigation as my only Telerik assembly. It worked fine in VS but opening in blend produced the error Ben found. If I added Telerik.Windows.Controls as a reference in VS I could open the page in blend.

Miroslav;

Thank you for the update and I'll download it now!
..Ben

New update works!

Thanks!
..Ben

Hi,
I was having the same problem as mentioned by Ben with "Telerik_RadControls_for_Silverlight_Beta2_Trial" .
I took the latest download "Telerik_RadControls_for_Silverlight_RC0_Trial".
Now I am not able to drag the TabControl on the Expression Blend 2.5 June 2008 preview. Every time I do it, I get the following error :

---------------------------
Target Invocation Exception
---------------------------
Inner exception: System.TypeInitializationException: The type initializer for 'Telerik.Windows.Controls.RadTabControl' threw an exception. ---> System.MissingMethodException: Method not found: 'Void System.Windows.PropertyMetadata..ctor(System.Object, System.Windows.PropertyChangedCallback)'.

   at Telerik.Windows.Controls.RadTabControl..cctor()

   --- End of inner exception stack trace ---
---------------------------
OK  
---------------------------

I have silverlight 2 Beta 2 on my machine and for Telerik have the dlls from the download of  "Telerik_RadControls_for_Silverlight_RC0_Trial".
Regards,
Sandeep

Sandeep, be sure have the following setup correctly:

.Net 3.5 SP1
VS 2008 SP1
SL RC0
Blend 2 SP1
Telerik RC0 compatible controls (latest one to pickup).

Try the tab with the above combo and see if you still have problem.