From all the information you have provided I assume there is something missing from the initial installation on your end. Since the .
Net 4.0 binaries are included by default when installing the demos I suggest you download the latest version and reinstall it. Please, update me if the issue persists after that.
In the meantime, what I can recommend is to install the SDK Samples browser
. With it you can navigate through the examples from our GitHub repository
which are more developer focused and should be of great help. They require the .40 binaries as well so the issue might still be present until you reinstall the UI for WPF.
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