No Event Log, aparece a seguinte mensagem: 00:56 Session 'app': Error Installing APK

Já no run, aparee a seguinte: com.android.ddmlib.AdbCommandRejectedException: device unauthorized. This adb server's $ADB_VENDOR_KEYS is not set Try 'adb kill-server' if that seems wrong. Otherwise check for a confirmation dialog on your device. Error while Installing APK

Saberia dizer como resolver?