I am attempting to install Windows 7 on a 2009 Mac Mini. I am using an external hard drive to install it using a disc. The installation went fine until Boot Camp rebooted my computer to Windows 7 (the disc). My screen transferred to a blinking underscore (or line, whatever). It remained like that for at least twenty minutes so I force-shut down my Mac Mini and held option to make sure that my computer booted onto the disc, but it the underscore still appeared. Am I not waiting long enough? Did I do something wrong during the installation? Do external hard drives not work for this type of installation? Any advice would be appreciated. Thanks in advance!