NI DAQPad-6016 DAQmx Error 50401

[Slight]

I am getting the following error when using the c library to communicate with my DAQPad-6016 (USB). Can someone shed any light on what this means:

DAQmx Error: An unknown or unexpected communication fault occurred while attempting to read data from or write data to a device.

Task Name: _unnamedTask(0)

Status Code: -50401

Unfortunately, the device is in our test jig offshore, so I can't run any of the NI utilities on it. I'd like to know if it is easy to fix before bringing the whole thing back to the office.

Thanks for the help

[EricS.]

Hi Slight,

I don't know of anything that would cause this error to just begin happening.  Did it just happen as you were writing new code?  Can you try running an example program or other code that you know works?  

I have also heard of this error happening when a USB device is plugged in to a USB hub, is that the case here?

[Slight]

This setup was working before and other identical jigs are working fine with the same code. It is not plugged into a USB hub. Can you tell me exactly what this error code means? From your response, it is sounding like it is some sort of hardware failure.

[Seth_B.]

That error code can be returned in a number of cases, but by far the most common is when the bus communication is interrupted or inoperative in some way.  In this case, there is probably an issue with the USB communication.  If it's possible to remotely reboot the test setup, that would be my first recommendation.  Do you have remote access of any kind to the system?  If so, and it is running a Windows OS, after the reboot I would make sure that the device shows up in Windows Device Manager.