The next step would be to contact Microsoft:
http://support.microsoft.com/kb/970892
How to obtain help and support for this security update

For home users, no-charge support is available by calling 1-866-PCSAFETY in the United States and Canada or by contacting your local Microsoft subsidiary. For more information about how to contact your local Microsoft subsidiary for support issues with security updates, visit the Microsoft International Support Web site: http://support.microsoft.com/common/....aspx?rdpath=4

North American customers can also obtain instant access to unlimited no-charge e-mail support or to unlimited individual chat support by visiting the following Microsoft Web site: http://support.microsoft.com/oas/def...spx?&prid=7552

For enterprise customers, support for security updates is available through your usual support contacts.