Avid ASIO won't initialize my hardware

I'm trying to use my Digidesign Accel hardware as a ASIO device with Studio One, Harrison MixBus3, etc, and none of the programs will initialize my hardware, making me use the built-in Realtek sound card.

I have Windows 7 64 bit and Pro Tools 10HD, HD3 Accel. I installed ASIO4ALL, and the Avid driver shows up on the list, but the hardware will not "initialize".

What is the trick to letting other software use my HD hardware? Thanks.

Avid ASIO won't initialize my hardware