Hi there, I need help with cleanup of an unsuccessful bluetooth pairing attempt: how can I remove remaining data from a pairing attempt, so that windows behaves like the way it sees the device the first time? Details: I have a bluetooth+trackboard keyboard type BOW HB087, windows 10 (several PC-s) is last x64 version, 1903 (or 2019 H1), German language. Pairing with an unseen PC works usually as follows: (1) switch on keyboard, engage pairing mode on BT keyboard (FN+C) (2) enter add BT device screen in settings in Windows (see screenshot "device list") (3) wait until "Bluetooth 3.0 Keyboard" is displayed as available device, and click on that device (4) an 8-digit PIN is displayed, See screenshot "PIN display" (5) enter PIN on BT keyboard, followed by ENTER (6) pairing completes In case something unexpected happens (in my case: weak battery in BT keyboard, reproduceable: keyboard is switched off before pairing completes), and a new attempt is startet, behavior changes after step (3): no PIN is displayed, but windows asks for a PIN to be entered, see screenshot "PIN request". On any PIN I tried, the answer was "wrong pin, try again". The generic BT help page of microsoft support mentions both authentication methods (enter PIN on BT keyboard or on PC), but does not tell details on the conditions for the PIN request type. See https://support.microsoft.com/de-de/help/14169/windows-10-fix-bluetooth-problems The keyboard manual describes only the usual pairing process and has no hints on error handling. I moved to another (unseen) PC, and tried pairing, it runs as usual (step (1) to (6)). Back to the pc with pairing problems. a pairing attempt again asked for the PIN, see screenshot "PIN request". I tried several times, even with the keyboard in normal (non pairing) mode and keyboard completely switched off. Curious: after switching off the keyboard, I can still try to pair, and the "enter pin" screen appears. With any PIN, some seconds later it closes with the message "device does not respond". After several such attempts, windows asks for a new PIN: However, after entering any PIN, an error message follows: I hoped this could reset the partial pairing - it did not. Conclusion: it's not the keyboard but windows, making the difference: windows remembers something of the pairing attempt. I doubt the keyboard firmware is smart enough to store host info and its PIN from interrupted pairing attempts. I looked for log info. Related events are in the system event log, but do not help (see event log screenshots). The Nirsoft "Bluetoothview" tool shows device arrivals and departures, corresponding to my attempts switching the keyboard on and off. See screenshot "nirsoft ...". O a successfully paired PC, I could remove the keyboard in the BT device list (screenshot "successfully..". Pairing again runs as usual (Step (1)-(6). I tried to remove the keyboard device on the PC with unsuccessful pairing. There is no entry in the BT device list. In the old device manager, it is not listed as well. I found one unused HID device in the keyboard and mouse sublists - but deleting both did not help. The device name "Bluetooth 3.0 Keyboard" was not found in the registry. And of course, I tried rebooting windows several times, and also removed the keyboard battery - the PIN request state is persistent. Any idea what I could do (except a clean windows setup)?