From: Georghy <fusco at wanagain.net> > what i have done : > creating a fat 32 partition on my USB key (4 GB) > tagging it with boot flag > copy MBR on the key : > dd if=/dev/sdb of=/tmp/mbr_sdb.bin bs=512 count=1 > Using syslinux : > syslinux /dev/sdb1 Your dd command seems to be reversed... You are taking the MBR from the key and putting it into a file... Instead of: dd if=/usr/share/syslinux/mbr.bin of=/dev/sdb Anyway, from your error message, you seem to start to boot... Did you modify your syslinux.cfg to have something like this? append initrd=initrd.img ks=hd:sdb2:/ks/ks.cfg method=hd:sdb2:/where_my_centos_iso_files_are Did you copy the CentOS ISO file(s) in /where_my_centos_iso_files_are/? JD