Bluetooth Won't Pair, Fix Pairing That Fails or Times Out
A device that appears in the Add device list but will not finish pairing is usually stuck on a stale pairing, a stopped Bluetooth service, or a passkey mismatch. The pairing handshake is short and unforgiving, so clearing both ends and starting clean fixes most cases.
Fix it, in order
Confirm pairing mode is still active. Pairing mode times out, often after a minute or two. If the scan has been running a while, put the device back into pairing mode and try again while the light is still flashing.
Remove the device from both sides. In Windows, go to Settings, Bluetooth and devices, Devices, select the three dots next to the device, and choose Remove device. On the device itself, or in its companion app, forget the PC as well. A half-finished pairing on either side blocks a new one.
Restart the Bluetooth Support Service. Press Win + R, type services.msc, and press Enter. Right-click Bluetooth Support Service and select Restart. Then restart the PC as well, so the Bluetooth stack reloads cleanly.
Try the pairing with the device close by. Keep the device within a few feet of the PC and away from other active Bluetooth devices during pairing. Interference from a nearby phone or a USB 3 device can corrupt the handshake.
Accept the passkey promptly. If Windows shows a PIN or a confirmation code, confirm it on both the PC and the device within a few seconds. Some devices use a fixed PIN such as 0000 or 1234, which the manual lists, and entering the wrong one fails the pairing silently.
Update or reinstall the Bluetooth driver. In Device Manager, expand Bluetooth, right-click the adapter, and select Update driver. If that changes nothing, right-click it, select Uninstall device, restart, and let Windows reinstall it.
Run the Bluetooth troubleshooter. Open Settings, System, Troubleshoot, Other troubleshooters, and select Run next to Bluetooth. It checks the service, the radio, and the pairing state, and can apply fixes automatically.
Pairing is not the same as connecting. A device can be paired and still need a tap on Connect before it works, and a device that pairs but will not stay connected has a different fix.
If it still happens
If pairing fails on the PC but works on a phone, the PC's Bluetooth stack is the problem, so a clean driver reinstall from the PC maker's site is the next step. If pairing fails everywhere, reset the device to factory settings using the procedure in its manual, since a corrupted pairing table on the device itself survives forget-and-repair attempts.
Common questions
Windows says "Try connecting your device again." What does that mean? The pairing handshake started but did not finish, usually because pairing mode timed out or the passkey was not confirmed in time. Remove the device, put it back in pairing mode, and try again immediately.
My device pairs with my phone but not my PC. Why? The phone pairing proves the device works. On the PC, the usual blockers are a stopped Bluetooth Support Service, an outdated adapter driver, or a stale half-pairing that needs removing first.
Do I need a PIN to pair? Some devices ask for one and some do not. Keyboards and headsets with a fixed PIN use 0000 or 1234 unless the manual says otherwise, and Windows shows a code to confirm on both sides for devices that support it.