1. unsigned IM(passthru) driver cannot bind to newly installed NIC
2. Uninstall a NIC in Device Manager, and re-scan hardware to re-insall it.
Unsigned IM(passthru) driver won't bind to the new NIC.
This is by design on XP.
Check setupapi.log, see the miniport driver server-side installation is blocked because of lack of driver signature.
#-011 Installing section [PassthruMP.ndi] from "c:\windows\inf\oem17.inf".
#E358 An unsigned or incorrectly signed file "c:\windows\inf\oem17.inf" for driver "Passthru Miniport" blocked (server install). Error 1168: Element not found.
#E122 Device install failed. Error 1168: Element not found.
Get WHQL signature or use test sign when testing.
Server side Install http://msdn.microsoft.com/en-us/library/ff541322(VS.85).aspx
Kernel-Mode Code Signing Walkthrough （http://www.microsoft.com/whdc/winlogo/drvsign/kmcs_walkthrough.mspx）