Yes, we're providing our assemblies built against .NET4.0 as well, their corresponding version is 2013.2.611.40.
If you've installed the RadControls for WPF, you can go to the installation folder ( C:/Program Files/Telerik/) and inside Binaries
folder there are WPF40
containing the dlls built against the corresponding framework . Even if you downloaded the assemblies as a ZIP file, the same structure is used. You will need to remove the current references in your solution and add them again, but this time from the WPF40
folder. Then clean and rebuild the solution.
I hope this helps.
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