I need help. Bought an old 2007 iMac with the flashing / blinking question mark folder icon. Used Command + R to boot up into Disk Utility (only worked by me creating a Bootable USB flash drive). Now in disk utility I have a problem... I can’t erase or partition Disk 1 or Disk 2 (please see attached Pic 1) and neither disks are even the actual 500GB internal HD which appears to be missing. I also can’t use a Bootable USB to install a fresh OS copy of Yosemite as there is no HD to select to install onto (please see attached Pic 2). Specs: iMac 24” 2007. 2.8GHz Core 2 Extreme. 2GB Ram. 500GB harddrive. It’s 2007 so I can’t use Internet Recovery at all. Thank you so much in advance!