How to fix Android BLE SCAN_FAILED_APPLICATION_REGISTRATION_FAILED error?

Question

Most of times it works great but sometimes i'm having this error while trying to discover BLE devices:

02-12 18:00:41.952  16178-16339/com.icrealtime.allie W/BleRpcConnectionFactory﹕ Starting discovery
02-12 18:00:41.955  16178-16339/com.icrealtime.allie D/BluetoothAdapter﹕ STATE_ON
02-12 18:00:41.957  24342-18813/? D/BtGatt.GattService﹕ registerClient() - UUID=c4a4c56d-1d10-4615-9c8d-44971bc3d6e6
02-12 18:00:41.957  24342-24384/? E/bt_btif﹕ Register with GATT stack failed.
02-12 18:00:41.957  24342-24384/? E/bt_btif﹕ Register with GATT stack failed.
02-12 18:00:41.957  24342-24370/? D/BtGatt.GattService﹕ onClientRegistered() - UUID=c4a4c56d-1d10-4615-9c8d-44971bc3d6e6, clientIf=0
02-12 18:00:41.958  16178-16190/com.icrealtime.allie D/BluetoothLeScanner﹕ onClientRegistered() - status=133 clientIf=0
02-12 18:00:41.967  16178-16178/com.icrealtime.allie E/BleRpcConnectionFactory﹕ BLE SCAN FAILED: 2

error code 2 stands for https://developer.android.com/reference/android/bluetooth/le/ScanCallback.html#SCAN_FAILED_APPLICATION_REGISTRATION_FAILED

It seems to be internal android issue, but it can be affected by my code doing something wrong. What can be the reason and how to walkaround it?

PS. Nexus 9, Android 6.0.1

Answer 1

I had the same issue and this worked for me. Might look like a silly fix but worked lol.

After adding the required Bluetooth and Location permission requirements in your manifest file...

<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION_LOCATION" />

You must turn on the FINE LOCATION or COARSE LOCATION permissions for the app. You could do this manually from the app settings on the device or add this bit of code to your onCreate() method.

if (ContextCompat.checkSelfPermission(this.getApplicationContext(),
                android.Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
        } else {
            ActivityCompat.requestPermissions(this, new String[]{android.Manifest.permission.ACCESS_FINE_LOCATION},
                    REQUEST_LOCATION_ENABLE_CODE);
        }

You'll also need to define int REQUEST_LOCATION_ENABLE_CODE as 1.