In order to make the auto size feature of the RadWindow control to work properly, you need to add this CSS declaration inside the head tag of the content page (the one which is opened in RadWIndow):
/* These settings are required in order to AutoSize to work properly */
html, body, form
In case, however, that the suggested do not help, could you please rework the attached sample in order to replicate the problem, open a new support ticket and send it back? Also, please send me some screenshots of the behavior on your side. Once I have a closer view over the problem that you experience I will do my best to provide a solution as soon as possible.
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