I have already answered your support ticket on the matter and I am pasting my reply here as well for others who may have a similar question.
I would like to ask that you do not post multiple threads for a single issue in the future, as this makes it harder to track the issue and conversation and also increases the response time.
I assume that you are using RadTabStrip in combination with a RadMultiPage in a way similar to this online demo
, just instead of images you put user controls in the RadPageViews. If this assumption is correct then the controls are part of the main page and there will be no issues in each user control having its own RadWindow with the static content you need (a simple example is attached and here is a video
that shows the modal overlay covers the entire page in this scenario). You could, alternatively, put a RadWindowManager on the page that has all the RadWindows that you need for this page, but this defeats the purpose of user controls a bit.
In case you are using PageViews with external content (i.e. iframes) it would be best if you declare the needed RadWindows in a RadWindowManager in the topmost frame (i.e. Page.aspx) so that they can cover the entire area. You could then call them by using window.top.radopen(null, windowName).
On a side note - I advise that you upgrade to the latest version of our controls and to a newer version of .NET, since the one you are currently using does not support IE9 and the .NET 2.0 framework is no longer supported
even by Microsoft.
the Telerik team
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