I am getting the same error message as follows: "The tag 'RadMenu' does not exist in the XML namespace 'http://schemas.telerik.com/2008/xaml/presentation'. I have been battling with this for a couple of days and it is bugging me big time. Now, I am running XP w/SP3 at work and I am running Win 7 32bit at home.
I did get the menus to work at home. I do have Telerik.Windows.Controls and Telerik.Windows.Controls.Navigation added as references. I even removed the references and re-added them to see if that would work.
I type in <telerik: in the xaml file and I see <telerik:RadHtmlPlaceholder and <telerik:RadNavigationButton but no RadMenu in between.
I have created a sample project and get the same error (thought it may be something in my main project, but I am getting the same thing in the sample (which is good - consistancy, and bad - darn, I was hoping it would work).
I am at home now and I copied the menu project that I created at work and all is ok. So, on my machine at home, with Win 7 32 bit Ultimate, VS 2010 Ultimate all is ok. But at work, with Win XP w/SP3 and VS 2010 Pro. I am not seeing the RadMenu. I go into the Object Browser and see the RadMenu under Telerik.Windows.Controls under Telerik.Windows.Controls.Navigation. Not sure what to add to try and help as I am baffled on this.
Hope you guys can figure something out.