Serial Ports Missing in NI MAX

Updated Aug 21, 2019

Reported In


  • Measurement & Automation Explorer (MAX)



Issue Details

  • When I open NI Measurement and Automation Explorer (NI-MAX), I am unable to see my computer's serial COM port.
  • In NI-MAX the serial ports are not available. I'm missing them from the Devices and Interfaces heading and I’m unable to create a new serial interface.
  • I was able to see my serial ports previously on this computer, but after OS updates, I can no longer see them.
  • I cannot select a serial port as a VISA Resource in LabVIEW.
  • In Device Manager, I can see my COM 3 port under Ports. But my serial COM port is missing in NI MAX.


This issue is generally caused by an improper installation of the NI-VISA driver.

To check if you have NI-VISA installed, open NI MAX, expand the Software tab, and check to see if NI-VISA appears as part of your installed software.

If you do not have NI-VISA installed, or you have a version earlier than 4.1, install the latest version of NI VISA.

If you have NI-VISA 4.1 or later installed, try repairing NI-VISA from the Control Panel >> Uninstall Programs options. If that does not have an effect, try upgrading to the latest version of VISA that is compatible with your operating system

In case you are confident that the latest version of the driver is installed you can also try adding the serial interface by hand in MAX. Follow the steps below to manually add a serial interface in NI MAX:
  1. Right Click on Devices and Interfaces under My System
  2. Create New...
  3. Select Port (Serial or Parallel)
  4. Click Next
  5. Select ASRL Number
  6. Select Serial Binding
  7. Click Next
  8. Define an Alias if you want to
  9. Click Next
  10. Click Finish

Additional Information

Without NI-VISA installed, MAX is unable to access or create serial, GPIB-VXI, or TCP/IP interfaces.

Note: Installing the NI-VISA Run-time Engine alone will not allow you to access or create serial interfaces in MAX; only the full version of NI-VISA will provide this functionality.

Please also note that in order to use NI serial devices with NI MAX the NI-Serial driver must be installed. To communicate with a device via GPIB, the NI-488.2 driver must be installed. Both of these drivers also include the NI VISA driver in their installation.

If you have tried these troubleshooting steps and are still unable to see your device, try force re-installing your VISA or NI-Serial or connecting to your device through a different computer.


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