Blue screen when booting from USB backup of Mountain Lion I've not been able to startup my MacBook Pro. I made a backup of Mountain Lion using Lion DiskMaker 2.0.2. When I press option and the power button then select the USB drive, the grey screen with the apple logo and spinner appears then shortly after I get a solid royal blue screen. Is there anyway I can boot from the USB drive backup to fix my computer?
Lion Disk Maker is a third-party utility. It’s likely that updates to OS X changed the startup behavior slightly for how your machine operates.

Any reason you wouldn’t use Recovery Disk? (Command + R on boot.)

You can also try booting to the USB drive, but enable verbose mode (before you select the USB drive, hold down Command + V) to see if there are particular errors shown when it is at that blue screen.

Last bit of hope: the author appears receptive to personal technical support questions by e-mail (that’s pretty cool).