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With the Q1 2010 release, RadComboBox.SelectionBoxItemTemplate property is read-only which breaks the Silverlight report viewer control template. To fix this issue, please download the latest internal builds for Telerik Reporting and RadControls for Silverlight (available in your Client.net accounts), build against the latest assemblies and clear your browser cache.
We apologize for the temporary inconvenience.
We apologize for the temporary inconvenience.