As of June 15, 2022, this site no longer supports Internet Explorer. Please use another browser for the best experience on our site.

Product Support

Product FAQs


When I plug my USB device into the UPort 400A or UPort 200A, why cannot it be detected by the host computer or recognized as an USB 2.0 device?


The Moxa USB hubs are all USB-IF certified (USB-IF TID: 7623 for UPort 407A, 7624 for UPort 404A, 7667 for UPort 207A and 7668 for UPort 204A); however, interoperability issues can still arise among devices made by different manufacturers. The chance of this happening is higher if your USB device is not USB-IF certified as over/under the SPEC design.

  1. Please ensure the UPort 400A/200A is recognized by the host computer.
  2. Plug your device into different USB ports on the hub to rule out that the USB port is damaged.
  3. Please check if it is a cable-related issue; change to a different cable to rule out a broken cable.
  4. Unplug the USB device or restart the device in computer management like Windows Driver Manager.
  5. For UPort 400A Series, please check if Over Current Protection LED is on, which may mean the downstream device is bargaining more power than it should. For UPort 200A, please check your computer screen if there is any error message that is or similar to “Unknown USB Device needs more power than the port can supply”. Withdrawing the device and re-plug in or providing external power to the device.

Relevant Products

UPort 200A Series · UPort 400A Series ·

Was this useful?
Rate this article
Thanks for rating our content. Any comments or suggestions?
Thanks for your feedback!
  •   Print this page
  • You can manage and share your saved list in My Moxa
Contact Moxa Support

Still need assistance with your Moxa product? Get help and save time by initiating an online support request and we will connect you to an expert.

Added To Bag
You have some items waiting in your bag; click here to finish your quote!