For a Bluetooth mouse in Windows 10, the fastest fixes are:
- Make sure the mouse is actually a Bluetooth mouse, not a USB receiver mouse. Some wireless mice use a USB dongle and will never appear as a Bluetooth device.
- Put the mouse back into pairing mode.
- Many mice require holding the pairing button for 5–7 seconds until the light blinks.
- If the light does not blink, check or replace the battery.
- Remove the failed entry and pair again.
- Go to Start > Settings > Devices > Bluetooth & other devices.
- If the mouse or the unknown device is listed, select it and choose Remove device.
- Then select Add Bluetooth or other device > Bluetooth and wait for the mouse to appear.
- If Windows asks for a PIN for the mouse:
- Check the mouse documentation or the device itself for a PIN.
- Try 0000 or 1234.
- If there is no place on screen to enter a PIN, type 0000 on the Bluetooth device and press Enter. This applies to keyboards; for a mouse, a PIN prompt usually means Windows may be detecting the wrong device or the mouse is not pairing correctly.
- Check the basics before pairing again.
- Turn the mouse off, wait a few seconds, then turn it back on.
- Make sure it is close to the PC.
- If possible, keep it away from USB 3.0 devices, which can interfere with Bluetooth.
- Charge the mouse fully or install fresh batteries.
- Restart Bluetooth on the PC.
- Go to Start > Settings > Devices > Bluetooth & other devices.
- Turn Bluetooth off, wait 10 seconds, then turn it back on.
- Make sure Windows 10 is updated.
- Go to Start > Settings > Update & Security > Windows Update.
- Select Check for updates.
- Restart the PC and try again.
- Select Start > Power > Restart.
If the mouse keeps appearing only as Unknown device and always asks for a PIN, that usually means one of these:
- the mouse is not in proper pairing mode,
- the battery is too low,
- Windows is detecting the wrong nearby Bluetooth device,
- or the mouse is not actually a Bluetooth model.
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