I am having the same type of problem with Telerik WPF controls.
I can see threads like this that are started and never resolved.
I am having trouble executing RadSplitButton and RadDataGrid in WPF.
The same error: Could not load file or assembly 'Telerik.Windows.Controls, PublicKeyToken=5803cfa389c90ce7' or one of its dependencies. The system cannot find the file specified.
I have added every single project reference that is included in the Telerik demos without resolving the problem.
I have tried changing my XAML reference from this:
with no success.
I do not want to, nor do I think I should need to fool around with my GAC. The Telerik install needs to set up my workstation in the best state for to adding Telerik controls into Visual Studio 2010 solutions. I figure that I do not need to do extra work.
Why are Telerik controls SO hard to use?