NOTE: This guide is for the following recorders : DVR-4480G, 4480RN, 4480V, 4580G, 4580RN, 4580V, 4680, 4680RN, 4680A, 4680X, 4680XN, 4685, 4685RN, 4780V, 4980, 5580, 5580A, 5580G, 5580G2, 5580RN, 5580RU, 5680, 5680A, 5680RN, 5680X, 5680XN, NVR-8580, 8580RN, 8780, 8780RN, NVW-650, 800
This error message means that the username and/or password you entered on the app doesn't match your recorder's credentials.
To resolve this, you need to go to the recorder itself and try to log in - this is to ensure that you have the right username and password of your unit.
Once you have it, you may try to add the device again and carefully enter its credentials on the app. In summary, you need to:
You may find this video useful but most importantly, you need to have your recorder's username and password with you as this is needed when pairing your recorder.