I had this problem when using EAC with XP. There isn't any ASPI support in XP as you're supposed to use the native NT calls. I also installed the Adaptec ASPI layer and it sort of worked but it was kind of flakey and would die every so often.

How did you install the Adaptec drivers? The package you get off the Adaptec page only lets you install if you've got Adaptec hardware.

- Trevor