WD15 Alienware 17r3 USB devices issue

Found some more interest points while trying to fix it:

USB 2.0 ports on dock station work only for charge device (mobile charge, other hub see power, but keyboard\mouse\headset still not work)

USB 3.0 devices work ok with USB 3.0 ports on dock.

USB 2.0 devices does not work in any ports.

On this laptop used other USB-C hub (HooToo), and it works ok (all devices ok).

I think there is issue with 2.0 drivers\FW of WD15, but can't update it :(

Also found that this dock work perfect on Macbook pro 13" 2016. So i'm sure that dock working, and i think that it is driver issue with my Alienware.

If USB 2.0 devices don't work anywhere and USB 3.0 devices don't work in 2.0 ports, then it sounds like you have a defective unit.  When USB 3.0 is in use (i.e. a USB 3.0 device connected to a USB 3.0 port), the connection uses the newer xHCI protocol.  When USB 2.0 is in use (i.e. a USB 3.0 device connected to a 2.0 port or a 2.0 device connected anywhere), the connection uses the older EHCI protocol, which is sometimes even handled by a completely different controller chip.  This wouldn't be a driver issue since there aren't any drivers required for the USB ports on a WD15 when you're running Windows 10, because Windows 10 has native support for USB 3.0 and 2.0, so the WD15's ports just appear as a USB hub.  It's not like the TB16 dock, where the USB ports are actually attached to a PCIe controller, which is why that dock requires a driver for its USB ports.

I would exchange the dock and see whether the replacement behaves properly.

How does it work with MacBook if decide deffective?

I missed that last post about the Mac, sorry. In that case, there is a WD15 firmware update from a while ago that you can try running, which you can find by going to support.dell.com and selecting the WD15 as your system (All Products > Electronics > Docks > WD15). And if you haven’t already, definitely update your system’s BIOS too, since that would update its USB-C controller firmware. If that doesn’t fix it, I’m not sure what to tell you because there are no drivers involved with making the USB ports work except the drivers already built into Windows 10. At that point if you really wanted to keep troubleshooting, I would consider capturing a full image backup of your system and then performing a clean install of Windows. If the dock works with the clean install, something was wrong in your system. If it still doesn’t work, then just restore your image backup to get back to where you were.

I think it's main trouble, that I can't launch update utility on my Alienware. Will try clean install or search anybody with XPS to update FW of WD15