I noticed I had another issue too that when I go into device manager, I was constantly refreshing after every little while. I had installed a USB bluetooth dongle as well after the fact which I have lost and it seemed a mashup. I had tried everything and I thought it will never work but finally got it to work! PS.: Both adapters are Intel 7620 AC and 1030 N. I haven't tried that, but this might also be worth a shot. Maybe it is also enough to remove the adapter startup Windows, shut it down and put in the adapter again.

So if you have a second one lying around and don't want to tinker with software methods which probably won't work if you your adapter disappeared in the device manager try this out. Another thing to note is that a driver update of either the WLAN or Bluetooth broke the Bluetooth functionality. This seems to be a bug within Windows 10 because I'm pretty sure this wasn't a connection issue since the WLAN worked flawlessly. I tried most of the above listed suggestions but none did help or brought it back to life. The switch for turning on Bluetooth was showing up again and it was also listed in the device manager.

So I disabled Bluetooth, turned of the computer and switched my other one (previously not working) back in and it started immediately working again. Strangly for me it did with my old adapter as soon as I booted into Windows again. Another thing to consider, if you have a spare WLAN adapter / card for your laptop.

Install bluetooth on windows 10 pc