以下是一些可能导致Bluetooth外设无法配对并提供解决方案的示例代码：

1. 检查设备是否正确配置：

if (bluetoothAdapter == null) {
    Log.e(TAG, "Bluetooth not available on this device");
    return;
}
if (!bluetoothAdapter.isEnabled()) {
    Log.i(TAG, "Bluetooth is not enabled, requesting user to enable it");
    Intent enableBtIntent = new 
    Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
   startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
   return;
}
if (bluetoothServerSocket == null) {
    try {
        bluetoothServerSocket = bluetoothAdapter.
               listenUsingInsecureRfcommWithServiceRecord(NAME, MY_UUID);
    } catch (IOException e) {
        Log.e(TAG, "IOException occurred while creating " +     
        "BluetoothServerSocket: " + e.getMessage());
        e.printStackTrace();
    }
}

2. 检查外设是否已注册：

if (bluetoothAdapter.isDiscovering()) {
    bluetoothAdapter.cancelDiscovery();
}
bluetoothAdapter.startDiscovery();
Set pairedDevices = 
bluetoothAdapter.getBondedDevices();
if (pairedDevices.size() > 0) {
    for (BluetoothDevice device : pairedDevices) {
        Log.i(TAG, "Paired Device: " + device.getName() + 
        " " + device.getAddress());
    }
}

3. 检查是否存在配对请求：

private final BroadcastReceiver pairingRequestReceiver = new 
BroadcastReceiver() {
    @Override
    public void onReceive(Context context, Intent intent) {
        String action = intent.getAction();
        if (BluetoothDevice.ACTION_PAIRING_REQUEST.equals(action)) {
            BluetoothDevice device = 
            intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
            try {
                ClsUtils.setPairingConfirmation(device.getClass(), 
                device, true);
                abortBroadcast();
            } catch (Exception e) {
                Log.e(TAG, "Error while autore-paring" + e.getMessage(), e);
            }
        }
    }
};
registerReceiver(pairingRequestReceiver, 
new IntentFilter(BluetoothDevice.ACTION_PAIRING_REQUEST));

4. 检查是否已经连接：

public