I recently bought my first MacBook Pro. Upon advice from friends I bought the base model, chose my own SSD and extra RAM with the intention of installing these myself. So I downloaded the installer for Mountain Lion as per many guides on the web. I've extracted the installer from the DMG onto a USB flash drive. I've now installed the new, clean SSD, inserted the flash drive, powered up and held the Option key. As anticipated I get the drive option screen showing the flash drive labelled as "Max OSX". However, this is when things start to veer off course. When I click on the Mac OSX option I'm taken to a new screen showing the Apple logo, the mouse pointer becomes a spinning icon, and after a few seconds the Apple logo becomes a grey 'no entry' sign, i.e. a circle with a diagonal line. I've tried it twice now and have left it for atleast 30 mins both times. Can someone please explain what's wrong (if indeed something is wrong) and what I need to do? Oh, one other thing is that almost immediately after going to the screen after the drive options, the light on the flash drive turns off and never comes back on. It's a USB 3 flash drive, but it's the same one that I used on the same machine to extract the installer from the DMG file.