After installing MS12-030, when you load an Excel workbook you may see the following error message: "This build of Microsoft Office is unsigned and cannot be trusted by a production Windows Rights Management Servicies (RMS Server). Before using Information Rights Management (IRM) in this build, specify a test RMS server."

This problem is caused by some specific files in MS12-030 being codesigned using a certificate that was incorrectly configured. The issue can be fixed by installing the hotfix package from http://support.microsoft.com/kb/2598144