Can not install from ftp.

Hi, Maybe I am stupid, but I have tried many times now, and allways end up with: "Installation system does not match your boot medium. Sorry, this will not work." I have downloaded tha latest beta 6 boot cd from the open suse site. When booting pu and pointing out the ftp server and directory, it ends up with the error message above after some time. What am I doing wrong? Regards Fredrik