GAMETRACKER could not scan a server on that port
one of the following suggestions may help you

your server is currently offline
gametracker needs your server to be online before you can claim ownership.
please restart your server and make sure it up before hitting claim server again

your server is firewalled
please turn off any firewall you have that may blocks scanning

if you are still unable to claim your server, you can visit the gametracker forums to get adittional help

Feel free to describe everything you've tried as well as the IP:Port of your CS server.