Thank you for the interest in our controls.
The cause for errors like the one you've observed is usually the ClickOnce cache, which you'd need to clear. Sometimes leftovers from previous installations could also cause problems like this, so we'd recommend fully uninstalling any older versions of the demos, if you have such, deleting the files if there are any left and clearing the cache before installing a new one.
You can find more information here
Please let us know if you've managed to run the demos successfully.
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