Can you try explicitly referencing the 1042's backplane when it's connected, even though it doesn't show up with viFindRsrc()? You should be able to find chassis information in Measurement and Automation Explorer
I tried to call the backplane on the PXI-1042 but that didn't work. I'm not using MAX. Then my program is loaded on to a computer it needs to be able to determine which PXI cage is attached. The PXI-1056 reports back its ID but the 1042 does not. How can I determine which PXI cage is attached just using calls is C++ not using max.