MAX Corruption or MXS Connection/Configuration Error Message on PXI(e) Real-Time Controller Boot

Updated Nov 19, 2018

Reported In


  • PXI Controller


  • LabVIEW Real-Time Module

Issue Details

My PXI or PXIe real-time controller displays one of the following error message during the boot process on the console:
[nidevldp––205––tDeviceloader.cpp––––––––––––] NIDEVLD Fatal Error: Failed to connect to MXS
[nidevldp––206––tDeviceLaoder.cpp––––––––––––] MAX configuration files may be corrupt
NI Variable Engine: Error: Unable to load the MXS configuration plugIn: Failed to get MAX Configuration interface for Tagger: 0x8004032a

​How can I restore the real-time controller to a working state?


This error message indicates that the configuration database may have become corrupt. This typically occurs in one of two scenarios.

One scenario is that the controller was working properly and suddenly gives this error. It is possible that the controller was powered off while the database was being written. In this case:
  1. Reboot the controller in Safe Mode. Consult the user manual for your real-time controller for instructions on how to reboot into Safe Mode.
  2. Open an FTP session to your real-time target.
  3. Open the folder /NI-RT/SYSTEM and delete the following files:
/ni-rt/system/*.mx5 (all files with the .mx5 extension in the directory)
/ni-rt/system/Last/* (all files in the directory)​​
  1. ​Reboot your real-time target without Safe Mode enabled. Consult the user manual for your real-time controller for instructions on how to do this.

The other scenario is that the error message appears after installing new software on the controller. In this case two options are available:
  • Reformat the controller and reinstall all software, driver-by-driver to identify any problematic software (recommended).
  • Uninstall all software on the target and reinstall it, one-by-one for each of the drivers. If uninstalling all software does not resolve the error, you'll likely need to reformat the controller.