unable to locate m-audio hardware

[uscbass]

I recently upgraded to pro tools 8.0.1 from pro tools 7. I have an M Box 2 Mini audio interface. The M Box worked fine with pro tools 7. Now when I try to open pro tools 8.0.1 it says "unable to locate m-audio hardware. Make sure your audio hardware is connected and turned on." The M Box is connected and is receiving power (green usb light is on in the front). I have tried disconnecting and reconnecting it and restarting the computer as well, nothing seems to work. I have seen several other posts with this same error message but they haven't helped me - they point to drivers for other audio devices. I can't seem to find any drivers or anything to download for the M Box 2 Mini.

I have an 2.8 Ghz with 4 gigs of ram intel Imac running Mac OS 10.5.8