I would suggest that you set the z-index of the RadWIndows the RadSocialShare uses to a higher value, because setting the z-index of the RadMenu to 0 is likely to break something else. You can use the following code to achieve this:
(rss1.FindControl(rss1.ID + "_emailPopup") as RadWindow).Style.Add(HtmlTextWriterStyle.ZIndex, "12345");
(rss1.FindControl(rss1.ID + "_compactPopup") as RadWindow).Style.Add(HtmlTextWriterStyle.ZIndex, "12345");
where rss1 is the ID of the RadSocialShare.
the Telerik team
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