unable to read group information from repositories. this is a problem with the generation of your install tree

I am getting the below error.

unable to read group information from repositories. this is a problem with the generation of your install tree

After the screen:

Install boot loader on /dev/sda/

Boot loader operating system list

    Redhat Enterprise Linux 6 /dev/mapper/Vg_rhel-iv_root

Version: Red Hat Enterprise Linux 6.4

Server : Dell T110 II  Server