When you setup a group policy that assigns internet settings located in User Configuration\Windows Settings\Internet Explorer Maintenance\Security\Security Zones and Content Ratings you have to copy your current internet settings to the GPO. These settings are useful if you wish to use the “preference mode” option so that the setting is set once and then the user has the ability to modify it from there. This all works fine when importing from IE6 but if you try to import settings from IE7 it will not work properly and you will get an error when trying to view the settings of that GPO:

“An error occurred while generating report:
An unknown error occurred while the HTML report was being created.”

There is rumor that this problem has been fixed in the Vista version of GPMC and I am assuming that this would include the server 2008 version but I have not tested this yet. A workaround as mentioned in the article linked below is to set the internet settings from here: User Configuration\Administrative Templates\Windows Components\Internet Explorer\Internet Control Panel\Security Page\Site to Zone Assignment List. This works great accept that you do not have the option to use the “preference mode”. [more]

http://sdmsoftware.com/blog/2008/03/gpmc_report_errors_related_to.html