Hello Jon!
I have a couple quick questions, and then a suggestion of something to try. First, which PCI-1394 card do you have, Adaptec (2 1394 ports) or Solectron (OHCI with 3 1394 ports)?
This may be an issue with conflicting versions of NI-VISA. Many of the new NI drivers (like NI-488.2) install NI-VISA 2.5, whereas NI-VXI 2.1 installs a previous version. When you look in Add/Remove Programs (under the Control Panel) what shows up for NI-VISA? Also, what version of Measurement & Automation Explorer is on the system? If it is version 2.0 or later, what drivers does it report having installed (under the software section on the left hand side)?
There is an updated version of nivxi1394k to be used with NI-VXI 2.1 for NT and 1394 and NI-VISA 2.5.
Please go to www.ni.com/ask and select to email support. From there, I will be able to send you the update to try.
Another thing to try: without running resman, open up VIC (VXI Interactive Control). From here, you can read the configruation registers for the VXI cards in your system. See if you get any errors from this, or if you can read the registers with out error.