The Problem

I recently rebuild my trusty Lenovo X1 Carbon laptop. As you usually find, a fresh install of Windows 11 meant a leap in performance.

All was good for a couple of weeks, until I started to get problems. It still was working to supply power and the HDMI connection to my external monitor worked, but the USB devices could not be seen.

I also checked with the Lenovo Dock Manager and it could now no longer see the dock.

The Solution

I am not sure why it happened, but the fix was

  1. Open Device Manager: Press the Windows key + X and select “Device Manager”.
  2. Show Hidden Devices: Click “View” in the menu bar and select “Show hidden devices”.
  3. Locate Thunderbolt Controller: Expand “System Devices” and find the “Thunderbolt Controller” entry.
  4. Uninstall: Right-click on “Thunderbolt Controller” and select “Uninstall device”. In the “Uninstall Device” window, check the box that says “Delete the driver software for this device”.

Once this was done I disconnected the dock and reconnected it, and this dialog appeared

Dock Dialog

I had to approve access to the dock.

My guess is that somehow this access control setting had got set in the wrong state. I have no idea how, as I was never shown this dialog after the Windows reinstall, but at least it is fixed now