Go on ATI's web site to the driver download section. Go to the "lowspeed" connection area and download just the driver, and control panel.
Once you have those downloaded, if you want to give it a shot, uninstall all your ATI software and reload those. You can uninstall ATI first through the Control Panel, Add/remove software, it will ask to restart. When Windows comes up, you can hopefully cancel the add new hardware thing, and install the drivers you downloaded.
If you don't want to do all that, re-enable the WDM, and maybe we can find another solution?