moving this to the Windows LE forum...
On the Featured Downloads page, under Quick Links in the Support section:
www.digidesign.com/downloads
...scroll down toward the bottom of the page to the Digidesign Audio Drivers > Standalone Windows Audio Drivers - ASIO & WaveDriver
The version that supports the original Mbox would be the Standalone Digidesign Windows Audio Drivers v7.4 for Windows. Qualified with XP and Vista, not tested with Windows 7.
There was no standalone version of the 8.0.1 drivers, and the 8.0.3 standalone drivers do not support the original Mbox.