Basically, if EnableViewState is set to true, all RadWindows' properties that are set from the server will be saved in the viewstate and applied again on the next postback. I am not quite sure that I understand your setup completely however, so at this point I cannot tell whether there is a problem with that property or not. If you believe that there is a bug in this functionality, please open a support ticket and send us a sample project so we can investigate further. Of course if there is a problem, we will do our best to fix it right away.
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