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Visitor II
January 7, 2025
Question

STM32 Virtual COM Port "Unknown USB Device" on one particular laptop

  • January 7, 2025
  • 2 replies
  • 1378 views

Hello STM Community,

I'm facing an issue with my STM32 device on Windows 11. The Virtual COM Port (VCP) driver is not working, and in the Device Manager, the device is shown as:
Unknown USB Device (Device Descriptor Request Failed)

Here are the details:

  • Device: own board
  • Troubleshooting Steps Tried:
    1. Uninstalled the STM VCP driver and restarted my PC.
    2. Reinstalled the VCP driver from the official STM website.
    3. Used a different USB cable and port (all working with other devices).
    4. Verified USB settings in the BIOS.
    5. Checked Windows Updates for driver compatibility issues.

Sujith_0-1736265817826.png

Despite these efforts, the problem persists.

Has anyone else encountered this issue with Windows 11? Are there any additional steps or settings I need to configure to resolve this?

Thank you for your assistance!

Best regards,
A.Sujith

    This topic has been closed for replies.

    2 replies

    Super User
    January 7, 2025

    Is this a VCP you are implementing, or the one in an ST-Link?

    Have you tried any other Windows version?

    Or any other OS?

    What hardware are you using?

    What software/middleware?

    What tools & versions?

    https://community.st.com/t5/community-guidelines/how-to-write-your-question-to-maximize-your-chances-to-find-a/ta-p/575228

    SujithAuthor
    Visitor II
    January 7, 2025

    This board works fine on other laptops and previously worked well on this laptop too. However, now the driver is not being detected. I uninstalled and reinstalled the driver, which temporarily fixed the issue, but the problem reappeared, and the driver is no longer working.

     

    Super User
    January 7, 2025

    @Sujith wrote:

    This board works fine on other laptops and previously worked well on this laptop too.


    So what's changed on that laptop?

    What's now different between that laptop and the others?

    (Thread title edited to clarify this).

    Technical Moderator
    January 7, 2025

    Hello,

    Are you sure you are using a good USB cable? try to change the cable.