there are NO updates for 6.5
the 6.5 repos were moved to "The Vault"
there should be a place holder now for 6.5
upgrade to the ONLY!!! supported version of 6
CentOS 6.6
Code:
su -
yum --relesever=6.6 upgrade
as to your current error
can you post the output of this command
Code:
su -
yum repolist all