On Friday, Microsoft issued a warning that as of December 11, 2009, customers using Microsoft Office 2003 have been unable to open or save Office 2003 documents protected with the Rights Management Service (RMS). On Saturday, the software giant released the following hotfixes for the issue: Office Client (KB978551), Word Viewer (KB978558), and Excel Viewer (KB978557). Office 2003 SP3 is required, though Microsoft recommends that only users who are experiencing the problem install the updates.

If you don't have the patch installed, when trying to open RMS documents using Office 2003, the following error message pops up instead: "Unexpected error occurred. Please try again later or contact your system administrator." The problem has just reared its head, over six years after the productivity suite was released, since a related Information Rights Management (IRM) certificate has only now expired.

Microsoft confirmed that Office 2003 products used in conjunction with RMS are all affected, including Word 2003, Excel 2003, PowerPoint 2003, and Outlook 2003. The good news is that Office 2007 and Office 2010 Beta are not affected and neither are earlier versions of Office (only 2003 and up support RMS). The software giant posted the following message on the Office Sustained Engineering blog on Friday: "We are working to resolve this issue as quickly as possible and we will provide customers a solution as soon as we can. Any new updates and we will post the information here." On Saturday, the blog announced that "The issue of the inability to open Office 2003 documents protected with RMS has now been resolved with a hotfix."

RMS is an information protection technology that works only with RMS-enabled applications to help safeguard digital information from unauthorized use. It uses encryption and a form of selective functionality denial for limiting access to documents and the operations authorized users can perform on them. RMS is often used to encrypt information stored in document formats and limit specific operations like printing, copying, editing, forwarding, and deleting. Policies embedded in the documents then prevent the content from being decrypted except by specified groups of people, in certain environments, under certain conditions, and for certain periods of time.

In short, the technology is targeted at large businesses, so chances are if you have Office 2003 at home, you're not using RMS and therefore need not worry. While Microsoft has not disclosed how many users are experiencing this problem, it is clear that the bug is stopping authorized users from opening their own protected documents, which is a huge embarrassment to the software giant. Thankfully, the company managed to get a fix out in under 48 hours.