Yep. So I don't think it's hardware. i.e., it's not a malfunction in the PCI bridge hardware itself. The hardware works, its drivers might be screwed up. It's an operating system problem or a permissions problem. Perhaps a bad file or setting in the operating system which prevents the device driver installation from proceeding.

My next step would be to google "code 28" along with the Plug-n-Play hardware identification numbers of the troublesome devices (Device manager, "Details" tab of the device, select "Hardware Ids"). See if others have had the same problem.