I had writen a WDM driver for ISA-device, and it worked good if there is only one device with the system.
But the driver can't support more than one device in the same system.
The error code is 31.

did there anybody ever had the same problem?

I use the LogConfig for ISA hardware configuration, and assigned Unknown to driver class.

Re: ISA NON-Plug and Play WDM Driver by Eliyas

Eliyas
Tue Jul 20 13:25:18 CDT 2004

Set a breakpoint in your AddDevice and see if that gets called. Most
probably your driver is failing AddDevice for the second instance.

--
-Eliyas
This posting is provided "AS IS" with no warranties, and confers no rights.
http://www.microsoft.com/whdc/hwdev/driver/kb-drv.mspx