By design only the Content is click-able - this way the alert can be dragged from anywhere else. However you could achieve the desired, but you would loose the drag drop functionality. What you need to do is to hook to the Loaded event RadDesktopAlert and set the CaptionHeight property of the parent WindowBase to 0:
sender, RoutedEventArgs e)
var parentWindow = (sender
parentWindow.CaptionHeight = 0;
Hope this helps.
Telerik by Progress
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