http://www.youtube.com/watch?v=uZaEs8lO-mM I get the exact same problem as in the YouTube video I tried several times to delete, format, partitiopate the hard drive but Mac osx installation make me restart all the time. I tried with Mac osx 10.6 and 10.8 from USB device and getting same error over and over again! Any solution please! Haven't tried with original snow leopard cd yet, but I'm afraid the error will come again. It's a iMac 21" from 2009 with preinstalled snow leopard the problem came when u tried to delete partition and install fresh copy of mountain lion.