Modbus Libraries (Versions 1.1 and 1.2) for older versions of LabVIEW (8.6 and older)

Updated Feb 22, 2024

Reported In


  • NI-Serial


  • NI Modbus Library
  • Modbus LabVIEW Library
  • LabVIEW Modbus API

Issue Details

  • I need an older version of Modbus LabVIEW Library. Can I get the old installers?
  • I need a file from the library ni modbus.llb. This library was part of older versions of the Modbus LabVIEW Library, however I cannot find this llb in recent versions of Modbus LabVIEW Library anymore. Where can I get it?
  • My LabVIEW program has a missing Modbus VI dependency. The name of the VI started with MB.


The latest versions of NI Modbus library can be installed through VI Package Manager as described here: LabVIEW Modbus API.

Older versions of the Modbus library are in the Attachments section of this KB. The 3 files contain the following:
    • Version 1.2.1 of the Modbus libraries.
    • Compatible with LabVIEW 7.1 to 8.6.
    • The recommended library for migration to later versions of LabVIEW.
    • The read me file contains installation details.
  • ni_modbus8_2.exe:
    • MSI installer.
    • Compatible with LabVIEW 8.2.
    • Modbus library version 1.1.
    • Compatible with LabVIEW 7.1.
    • Contains installer.
Note: NI does not support older Modbus libraries. They are provided as-is, to allow developers to maintain existing LabVIEW applications. New applications should use the current version of the Modbus libraries.

Additional Information

The source code of the current LabVIEW Modbus API is hosted on an external GitHub repository: NISystemsEngineering/LabVIEW-Modbus-API