I have never seen such behavior with RadWindow before, neither with older versions, nor with 2012.2.912, nor with the latest 2012.3.1308. Have you tried the latest to see if you still have the same behavior?
What I can advise is that you try the following suggestions in the meantime:
- make sure your browser is not zoomed. Usually View -> Zoom will show a list, select 100% and see if this fixes the problem
- try removing all custom CSS you have on the page in case some rule there is interfering with RadWindow's markup. If this fixes the problem you can start slowly re-adding your rules to find the cultprit, then make it more specific so it will not affect RadWindow
- remove all custom code related to RadWindow to see if something you have added is causing this
If you are still unable to resolve this I advise that you post the minimal code that reproduces the problem on your end so we can actually inspect this case.
the Telerik team
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