Invalid device ID

[johnmountney]

I am trying to use the NI-8451 I2C/SPI device. The device was previously working properly . However, I now get an invalid device ID error. What would be the cause of this and what is the solution? The green LED is blinking as expected. NI MAX says the device is working properly and I that I should be able to communicate with the device.  The device ID that shows up in NI MAX is the device ID I provide to the NI-845x Device Property Node. I have tried closing LabVIEW and restarting y PC. The error message I get is:

Error -301706 occurred at NI-845x Close Device Reference.vi:1

Possible reasn(s):

NI-845x:  The device reference is invalid. Verify that the supplied device reference contains a valid device name.

Any help is appreciated. Thank you.

[JÞB]

Lets see what happens if I shake the 8-Ball, Sometimes it works
~~~~~~~~Oh 8-Ball ~~~~~~~~

Did a For loop output an empty I/O Session?

Look through your code for 0 iteration for loops (or auto-indexed for loops that may have an empty array) that pass the I/O session on tunnels and replace the tunnels with a Shift Register.

Without seeing the code I can only guess but, that magic 8-Ball sits next to me for a reason.