You can try the installation for Silverlight 3 from our Q1 2010 official release.You can find it here
. Also you can take a look at our Silverlight 3 online demos here
Besides RadControls for Silverlight 4, RadControls for WPF 4.0 can be used only in Visual Studio 2010.
Here at Telerik we understand the difficulties when some developers should move from VS 2008 to VS 2010. That is why, we did our best to keep Silverlight 3 support from more than six months after the official release of Silverlight 4. I should say that this is pushing our developers and infrastructure to their limits and other aspects of our business are already suffering. This is the main reason for discontinuing any support for RadControls for Silverlight 3 with our Q3 2010 release.
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