You develop a web application that uses global variables. Under certain conditions in Windows Internet Explorer 9, a given variable seems to be undefined or inaccessible, especially in very quick looping calls. When the issue occurs, the web application throws an exception that indicates that the global variable is not defined or is inaccessible from the child window.
This issue occurs because of a problem in the script engine of Internet Explorer 9.
To resolve this problem, install the update that is described in this section.
Security update information
To resolve this problem, install the most recent cumulative security update for Internet Explorer. To do this, go to the following Microsoft website: