I can't seem to be able to install Windows 7 64-bit on a 2008 MacBook (64-bit dual core) from an external USB DVD drive. I've done the following: Performed a clean install of Mac OS X Snow Leopard Installed all system updates Run Boot Camp Assistant - when the system restarts I get an error stating "no bootable disc" Used rEFIt, but I still get the same error Made a bootable USB drive from an ISO of the Windows 7 installation disc, but I still get the same error Tried using Windows 7 32-bit, Windows 7 64-bit and Windows XP, but I still get the same error How I can resolve this?