Unknown server tag ‘asp:SearchExpression’ error with QueryExtender control in Visual Studio 2010 Beta 1

One of the cool things about ASP.NET 4.0 is the Query Extender and the ability to search within DataContext without using WHERE clause, writing extensive code etc.,  It works on the new set of namespace i.e. "System.Web.UI.WebControls.Expressions" namespace.

I am trying to put up an extensive sample using QueryExtender in the next post, but for this post, I wanted to share an error that yo...Full Article.