I believe this to be a bug in IE: http://support.microsoft.com/kb/2833068
. RadWindow is a div that holds a table (the table creates the layout - titlebar, borders, statusbar) and inside an iframe that hosts the page/pdf. IE seems to have a bug in this scenario that requires certain updates to be installed. The issue is that this bug is actually supposed to be fixed with the following update: http://support.microsoft.com/kb/2817183
. The "Non-security-related fixes that are included in this security update" section lists this bug as fixed, but the line above the table reads "Individual updates may not be installed...." which makes it hard to determine if the fix is actually present on any given machine. We have also had reports that this update is what actually introduces the bug in the first place.
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