Deployment and Scan Mode Errors Using EtherCAT on Default Ethernet Port

Updated Sep 28, 2022

Reported In


  • Industrial Controller
  • CompactRIO Chassis


  • LabVIEW


  • NI-Industrial Communications for EtherCAT

Issue Details

I am running into errors when deploying my code to an Industrial Controller. What do these errors mean and how can I resolve them?

Related Errors

After Successful Deployment 

An error occurred while attempting to switch the I/O scan mode. 

The slave device deployed to the real-time target does not match the device in the EtherCAT network. The mismatch happens if a slave device has been inserted, removed, or substituted after deployment. Redeploy the device to ensure that each device in the network matches the device in the LabVIEW project tree.

Deployment Error

LabVIEW: (Hex 0x80DF0002) A File I/O error occurred

After Refreshing Modules in NI Distributed System Manager

Error -66226 : Contact National Instruments - Incorrect use of internal API for IO variable


  1. The primary Ethernet port on an NI Industrial Controller cannot be used for EtherCAT communication. One cause of the errors mentioned above is attempting to use the primary Ethernet port for EtherCAT communication. You can check which Ethernet adapter is primary in NI MAX by navigating to the Network Settings tab (see screenshot below). 

Additional Information

Please be aware that these errors can occur in other contexts as well. Here are some general troubleshooting steps to take if the above solution is not applicable to your situation. 

•    Reformat controller (may resolve hardware issues)
•    Undeploy the old configuration, rebuild the application, and redeploy everything to the target (may resolve software corruption)
•    Tried switching to active mode (enables connection to the network)