Error 56: Timeout When Communicating Between VeriStand and Network Devices

Updated May 11, 2020

Reported In


  • VeriStand

Issue Details

I am trying to talk to deploy a VeriStand project and I get an error message.

The VeriStand Gateway encountered an error while deploying the System Definition file.
Error 56 occurred at Project Window.lvlib:Project >> Project Window.lvlib:Command >> NI_VS Workspace ExecutionAPI.lvlib:NI VeriStand - Connect to
Possible reason(s):
LabVIEW:  The network operation exceeded the user-specified or system time limit.



This timeout error can be caused by configuring the TCP/IP functions incorrectly, and can often be cleared without detriment, as long as the data is being received. If the data is not being received, there are several troubleshooting steps below to mitigate this error.

  • Try deploying a blank System Definition by only specifying the controller settings.
  • Ensure you have the appropriate drivers for VeriStand listed in the VeriStand Readme
  • Ensure that the correct IP Address and Controller OS are specified in the System Definition.
  • Ensure that the network cable is properly connected to each system or that the wireless network connection is properly established.
  • Try a direct Ethernet connection between the host PC and RT Targets if possible
  • Try to reach the network devices in question with a ping command in order to verify that the devices are still connected and communicating.
    • The response time should be minimized to ensure that VeriStand has enough time to deploy necessary dependencies like Custom Devices.
  • Turn off all firewalls and antivirus software packages installed on the host computer to ensure no ports are blocked.
  • Make sure that both devices are on the same subnet, and have the same subnet mask. See "Inconsistent IP Settings" When Connecting to Real-Time Target in NI MAX for more information on configuring NI network devices.
  • Check if excessive local network traffic has slowed your network communication and caused transfers to take longer than expected.

Troubleshooting Using Packet Sniffing:

If the above steps do not help, use a packet sniffing program to see if the data is being sent across the network. A third party tool called Wireshark can help you see if the data is arriving. If no data is arriving and you see this error, there is a problem either on the device sending data, or with your network. If data is arriving at Wireshark, and you still see this error, most likely you have a firewall issue or malformed TCP functions. Wireshark is available at Wireshark.  You can use Capture Filters with Wireshark to help isolate packets only going to/from a certain IP address.

Additionally, if the packets do successfully get sent out to the network, but the end device does not respond, there is a chance that the network adapter of the end device is defective.

Additional Information

Error 56 is caused by the code not receiving a network response within a user defined time limit. This error is a generic timeout error and can be the result of a lot of different factors.