My MacBook (running Lion) will not boot and goes into OS X Recovery.... I think because I let the battery completely run down, although that could just be a coincidence. Disk utility "sees", but finds no problem with the HD. When I try to reinstall from Time Machine, the hard drive does not show up as a location option (only the other partition on my external BU drive is visible). My first question is why is my HD not showing up as an option? The second question is whether it would be advisable to erase the HD and see if it then shows up as an installation option in OS X recovery before taking it to a shop?