Wayne,
If you have the NI-DMM driver fully installed, then it should be
detected automatically.  Are you working with a PCI DMM or a 
PXI DMM?  Which model are you using (4060, 407x)?
Check in Windows Device to see if the device is recognized there.
- If it is not recognized in Device Manager, then try to reseat the
card in its PCI/PXI slot, or switch slots.  Windows will not be
able to assign the proper driver if the card is not visible in the
system.
- If it is recognized in Device Magager, then right click on the device
and choose "Update Driver..." and have Windows search for the
appropriate driver (NI-DMM).  If Windows says that it can't find
the appropriate driver for the device, then I would recommend
uninstalling and reinstalling the NI-DMM driver.
Let me know if this helps.  Good luck!
Travis W