M-Audio Delta 44 won't work with PT9. Help?!?

We have a Dell PC running ProTools with a delta 44 card. The card works with every other program we have, just not ProTools. We have tried drivers version 5 and the recent 6.0.8, but selecting the Delta in the Playback engine menu gives us a warning that it cannot initialize the driver.

We are running..
Win 7, no service pack
Dual 2.93 GHz intel core 2 duo
4Gb RAM
32bit