Just bought a mac mini server 2012. Some how its set up so you can not use an external hard drive on it . or change the hard drive for that matter. it boots to the original ok but i replaced it with an SSD that i know boots and got a ?. put it in the usb and held option it doesnt show up. doesnt show up in start up disk or on my dektop either but it does show up in disk utility and I know it works fine I booted two other macs off it with no problem. Does that fact that its a mac mini SERVER make a difference? Does any one know i can turn off dont boot from usb some how ? Suggestions please. and thank you