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

Updated Sep 16, 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?
  • What driver is needed to interface with my USB-232 device?


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

If issues persist, you can also try the following:
  1. Repair NI-Serial.
  2. Force reinstall NI-Serial.

Additional Information

Your NI serial device may be showing up in Windows Device Manager, but 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.


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