System hanged after configuring Modem

I’ve a ISDN Modem “SANTAS communicator” problem is when ever I configue that Modem with any System its screen goes Blue and an Error message displayed:

*** Stop 0x0000000D1 (0x00000008,0x00000002,
0x00000000,0xBFE38F3O)

DRIVER_IRQL_NOT_LESS_OR_EQUAL

*** Adress BFE38F30 base at BFE27000, DataStamp
3cf79a84 – VMdmc.sys

I taked following step to find out the Error:

1- I changed the system
2- reinstalled the OS ( windows 2000 Pro )
3- scanned for virus

but Error is still there.

Note: its not happening frequently it may takes
couple of hours or one or two days. I m
also running Proxy server ( Kerio WinRoute
Pro)