Security Update SecUpd2012-004.pkg not downloading

Hi

My mac book pro 13" mid 2009 10.6.8 tried to update the software today and could not find "security update 2012-004.pkg as the file could not be found on the server "swcdn.apple.com". Shows Size of the file as 269.9 mb and time to download 2147483648 hours!!!!! help!