mbox 3 in pro tools 10 issues

I seem to be having trouble locating my mbox inside of pro tools. All drivers, plug ins are working correctly and the mbox plays sound back through every software in the computer besides Pro tools. I tried reinstalling everything and that didn't help. Everything use to work great and now Pro tools will not recognize the mbox in the hardware or playback engine no matter what I try. any idea what the problem may be?! thank you!