CentOS 4.2 final update

i cannot update my centos box here is the error:
Setting up Update Process
Setting up repositories
http://mirror.centos.org/centos/4/updates/i386/repodata/repomd.xml: [Errno 4] IOError: <urlopen error (-2, 'Name or service not known')>
Trying other mirror.
Cannot open/read repomd.xml file for repository: update
failure: repodata/repomd.xml from update: [Errno 256] No more mirrors to try.
Error: failure: repodata/repomd.xml from update: [Errno 256] No more mirrors to try.


can you tell me how to solve this problem?thank you

 

Please don't double-post: http://www.howtoforge.com/forums/showthread.php?t=14681