several attempts to install windows vista 64 ultimate have resulted in the\nerror message: "windows cannot install required files. the file does not\nexist. make sure all files required for installation are available, and\nrestart the installation. error code: 0x80070003". i've tried installing\nfrom the dvd-rom, and from a copy of the dvd-rom on my hard drive, each\nseveral times. please help.