Commented Issue: CollapsiblePanelExtender Loses Session in IE8 [27182]

If your CollapsiblePanelExtender's ImageControlID points to an ASP:Image control that does not have any ImageURL specified then it will cause IE8 to lose all session variables. The problem does not occur in IE9 or FF. The simple fix is to insure that your ImageControlID target has its ImageURL specified. You can use the ExpandedImage or the CollapsedImage. There is a temptation to skip the ImageURL because the CollapsiblePanelExtender automatically sets this value.
Comments: Problem did not show up on development machine. Only manifested after published to IIS7 server.