I hope this is a appropriate place for this request. I have a boot USB stick that presents a menu with various OS's and utils. I didnt compile the USB disk, but copied at a block/raw level using ddrescue from a friend. It works well from him. On some computers it fails after selecting a OS to install with the same message: ***************************************************************** Booting Windows 7 x64 Autodetect number-of-heads failed. Use default value 2 Autodetect sectors-per-track failed. Use default value 10 Address 0x8280: Value 0x80 Address 0x8280: Value 0x80 Load segment: 0x0 System Type: 0x0 Sector Count: 0x8 Load RBA: 0x2DE Boot Type: 0 = No Emulation Press any key to boot from CD or DVD **************************************************************** It then boots from the Hard Disk.... The commands behind the Win 7 install menu are: map --mem (md)0x800+4 (99) map /Boot/Win7-x64.iso (0xff) checkrange 0x80 read 0x8280 && map (hd0) (hd1) checkrange 0x80 read 0x8280 && map (hd0) (hd1) map --hook write (99) [FiraDisk]\nStartOptions=cdrom,vmem=find:/Boot/Win7-x64.iso:\n\0 chainloader (0xff)/BOOTMGR || chainloader (0xff) Interestingly there are some other utils on the USB stick (like Acronis) which show the same message, but nevertheless boots. Any help greatly appreciated. I can provide BIOS information for computers on which it fails if thats of any help. -Al