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mr_jrt · 01-03-2022, 09:49 PM

I've experienced this for quite some time (as in, years) and never quite gotten around to reporting it, but here I am now, so better late than never. I can't comment if these problems exist with other operating systems' versions of the drivers, but I can confirm they persist with my Win10 installation, and I used to experience them with my old XP install back in the day.

Basically, if the DisplayLink box is already connected to the monitor when the USB is subsequently connected, it will fail to initialise. Windows 10 will detect the device (as "USB Graphics Adaptor", IIRC), install the drivers, then the device will disconnect. Windows logs state the device failed to initialise. It will sit there connecting and disconnecting ad-infinitum.

However, if you disconnect the device from the monitor and USB, then plug in the USB cable, and then finally reconnect the monitor, the device initialises and works fine. The devices reappear as "USB Adaptor".

I have two old USB 2.0 dongles, and a newer Dual USB 3.0 dongle. I've not tested the problem with the newer Dual device yet.
Old devices are USB\VID_17E9&PID_0199&REV_0108

This use case came about again as I have a new USB KVM switch, and I've been troubleshooting changing my connections around over the last few days, and it has reminded me of this problem whilst troubleshooting.

FWIW (and mentioned only as a ancillary bit of information), as part of my troubleshooting I tested them on a Linux box, and the UDL driver was reporting the monitors returning completely empty EDID data and so they failed to initialise there, with this failure state persisting across reboots and disconnections. Plugging them into a Windows laptop without a monitor attached reinitialised them and they subsequently worked on the Linux machine as expected. I'm not sure if your ICs hold some kind of state internally?

01-03-2022, 09:49 PM	#1
mr_jrt Junior Member Join Date: Nov 2012 Posts: 3	Win10 Driver problems I've experienced this for quite some time (as in, years) and never quite gotten around to reporting it, but here I am now, so better late than never. I can't comment if these problems exist with other operating systems' versions of the drivers, but I can confirm they persist with my Win10 installation, and I used to experience them with my old XP install back in the day. Basically, if the DisplayLink box is already connected to the monitor when the USB is subsequently connected, it will fail to initialise. Windows 10 will detect the device (as "USB Graphics Adaptor", IIRC), install the drivers, then the device will disconnect. Windows logs state the device failed to initialise. It will sit there connecting and disconnecting ad-infinitum. However, if you disconnect the device from the monitor and USB, then plug in the USB cable, and then finally reconnect the monitor, the device initialises and works fine. The devices reappear as "USB Adaptor". I have two old USB 2.0 dongles, and a newer Dual USB 3.0 dongle. I've not tested the problem with the newer Dual device yet. Old devices are USB\VID_17E9&PID_0199&REV_0108 This use case came about again as I have a new USB KVM switch, and I've been troubleshooting changing my connections around over the last few days, and it has reminded me of this problem whilst troubleshooting. FWIW (and mentioned only as a ancillary bit of information), as part of my troubleshooting I tested them on a Linux box, and the UDL driver was reporting the monitors returning completely empty EDID data and so they failed to initialise there, with this failure state persisting across reboots and disconnections. Plugging them into a Windows laptop without a monitor attached reinitialised them and they subsequently worked on the Linux machine as expected. I'm not sure if your ICs hold some kind of state internally?