I have erased my MacBook's hd containing the OS, the problem now is I can't install a new OS. My installer CD is not the one the was shipped with my mac. My MB doesn't detect bootable usb as well. I don't know if there was a problem when burning the disk image to the usb or is it my mac that has the problem. Please help me as my MB is really unusable right now. What apps can I use to make a bootable USB on windows for mac? And what should I do to install os to my old MacBook 2007?