I am trying to load windows 7 on a new Mac Air(OS X 10.9 Mavericks) using Boot camp, a downloaded windows 7 iso file, and USB3 flash drive. No obvious issues with stepping through the initial phases of boot camp and disc partition, but when the system reboots to load windows setup/install from the USB3 flash, it stalls after a few screens and gives a "missing cd/dvd drive" error. I have read similar posts regarding this fail that imply there is possibly a windows 7 compatibility concern with USB3, and that if a USB2 port is available....or if you can change your BIOS to make your USB3 look like USB2...then you can get around this error. Unfortunately I only have USB3 ports on this system, and it appears accessing the PC equivalent "BIOS" on the new Macs is very difficult....and if you screw it up you can ruin the system. Does anyone have any suggestions? I should also mention that there is NOT a CD/DVD drive on the Mac Air....and I can't migrate to Windows8 (for various reasons). Any help is much appreciated!!