I saw the office 2007 updates come down on a machine that had never had office 2007 on it. The cause was easy to track down to the compatibility pack that allows edits of office 2007 files in office 2003.
I have a Vista notebook that came loaded with Office 2007. I deleted it and installed Office 2003. Microsoft Updates sent me three updates for Office 2007. Is it safe for me to just ignore them or should I accept them?