My USB-232/4 Is Not Recognized in MAX or Windows Device Manager

Updated Aug 1, 2019

Reported In


  • USB-232/2
  • USB-232
  • USB-232/4
  • USB Cable


  • NI-Serial

Issue Details

  • After updating my laptop, I can no longer see my NI USB-232/4 in NI Measurement and Automation Explorer (NI MAX). The device shows up in the Windows Control Panel as 'NI USB Initialization' and there is a yellow triangle warning sign next to it.
  • I'm setting up a new PC and have installed NI-VISA 19.0 and opened NI MAX. But when I connect my USB-232, it's not recognized in MAX, and Windows doesn't load a driver. How do I fix this?
  • I am using an NI Serial device and it is not showing up in Windows Device Manager, nor in MAX. How can I fix this?


The issue can often be resolved by simply updating to the newest version of NI Serial. This is the driver that allows your computer to communicate with the device via the USB-232 cable.

If issues persist, you can also try the following:
  1. Repair NI Serial
  2. Force reinstall NI Serial
  3. Upgrade to a later version of NI Serial

Additional Information

Your NI Serial device may be showing up in Windows Device Manager, but is hidden. To see it you will need to open device manager, select View >> Show Hidden Devices, and now you should see the serial device. If it has a yellow exclamation mark and is grayed out, manually associate the device to the NI Serial driver.


Not Helpful