Windows Hello "Couldn't turn on camera"

The embedded Windows Hello Face sign-in in Windows 10 is a amazing feature that it can unlock the computer by your face in no more than one second. But sometimes it doesn’t work properly on my laptop,

Case 1

Windows Hello Face sign-in does not work, even if roll-back the device driver. This is due to the webcam protection module of ESET Internet Security blocked the access privilege of svchost.exe to the IR camera. If the Windows Hello still can’t be enabled even the webcam protection has disabled, try the following procedure.

  1. Re-install the ESET Internet Security suit.
  2. Turn-on Windows Hello face sign-in.
  3. Press Win + L to lock screen and then unlock screen via Windows Hello. After that, the svchost.exe will be added to the whitelist automatically.

Case 2

Updated in 2019-12-21

When digging into the “Device Manager”, there is an unknown device in the “Other devices” subgroup, which is the missing IR Camera that used belong to the Cameras group. When it was clicked, a “device descriptor request failed” prompt will be given. This problem may be commonly encountered when the laptop recovered from sleep mode.
Solution: Just right-click the unknown device then uninstall it. Moreover, click “Scan for hardware changed” in the toolbar, then Windows will automatically install the driver for it. After that, the face sign-in will be back to you when the IR Camera appears in the “Cameras” subgroup again.