A little late posting this, but better late than never. In December, an issue surfaced that prevented Office 2003 documents from being opened, if they were protected by Rights Management Server (RMS). The issue was due to a time-bomb… oops.
Users would get a prompt that stated: "Unexpected error occurred. Please try again later or contact your system administrator"
Microsoft quickly released a hotfix over that weekend, but now the fix is pushed down through Windows Update.
This is only for Office 2003, and make sure that you have Service Pack 3 installed prior to installing the update.