plafuro

Hi guys !! I downloaded the raw tree availabre now on the mirrors, and im trying to create a bootable installation dvd... the poing is that when using the cdrom.iso boot image to boot the dvd, the installation starts, but i get the message "That CDROM disc does not seem to be a Mandrake Linux Installation CDROM. Retry with another disc?". Any ideas? Thanks in advance :)