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Dear Microsoft community,
I am reaching out for help regarding an unexpected error we have encountered using libusb on Windows.
Regarding the issue: “Randomly,” with our custom USB device, libusb reports a systematic failure when attempting to set the device to a specific alternate setting. When setting the log levels to debug, the following issue is reported: “libusb: error [winusbx_set_interface_altsetting] SetCurrentAlternateSetting failed: Insufficient system resources exist to complete the requested service.”
I have looked into existing topics regarding this issue but found none answered, at least related to USB. Usually, the issue appears to be more observable on computers that are not often turned off, but we have had the issue at least once on every computer using Windows (only tested on Windows 10).
I believe that the issue is not related to libusb itself according to the error reported but to WinUSB.
What has been tested/verified:
We are looking for some explanation of what might be causing the issue, if it is known, and if there is any workaround that we could implement.
Thank you in advance for your answer.
Best regards.
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Hi Fourcade, Pierre,
Thank you for posting in the Q&A Forums.
Free up system resources:
Restart the computer to free up memory and USB bus resources.
Close unnecessary applications and services to reduce system resource usage.
Update or reinstall WinUSB driver:
Visit Device Manager, locate your USB device, right-click and select “Update Driver”.
If updating the driver does not work, try uninstalling the device and restarting your computer to let Windows reinstall the driver.
Check for hardware conflicts:
Check if any of the devices are labeled as conflicting or faulty in the Device Manager.
Try disconnecting other USB devices and connecting only your custom USB device to see if the problem persists.
Use another USB port or computer:
Try connecting your USB device to a different USB port or another computer to see if the problem is caused by a specific port or computer.
Best regards
NeuviJ
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If the Answer is helpful, please click "Accept Answer" and upvote it.
Dear NeuviJ,
Thank you for your response.
While your solution for freeing system resources is something we implement during development, it is not viable for us in production. We plan to deliver our USB device for integration into complex systems, and it is not practical to ask our customers to perform such cleaning when the error occurs sporadically. Restarting the computer or changing the USB port does not resolve the issue; the only solution is to uninstall the drivers and then restart the computer.
According to Device Manager, there is no conflict with the device. Enumeration is correct, and as long as we do not attempt to set the alternate setting, the device responds and behaves correctly.
I am also discussing this issue with the libusb community. They suggest that it could be related to a request exceeding the allowed bandwidth on the USB controller. We are requesting isochronous transfers of 300MB/s on this setting, so we should be fine since nothing else is connected to the computer.
Is there any way for us to check the resources around the USB on the Windows side to determine if this is indeed related to a bandwidth request issue?
Thank you in advance for your help!
Best regards,
Pierre