1- I know with 100% certainty that when you plug a new Dahua camera into a newish Dahua NVR PoE port, it will adopt the login/pass of the NVR
2- if I then login to the camera via the blue IE icon while connected to the NVR and change the password, it will save and it will pass that new password to the NVR. I can close the camera GUI , login back in with the new password ****as long as I dont unplug the camera or reboot the NVR.
3- if I then unplug the camera from the NVR and plug it back in, and wait for it to be recognized by the NVR by itself, ( patience is key here, it can take a minute or 5 min, don’t force it. Go have a smoke and just friken wait!) it has a red indicator and Can Not be accessed via the blue IR icon.
4- The NVR did not save the new password. So I click the pencil icon, edit the new password credentials I assigned the camera, hit save and refresh and the indicator turns green and I can once again and forever afterward access the camera from the IE icon using the new password I set in step 2
So what this tells us is that after changing the password on the camera from the original set by the NVR, you must go back to the pencil Edit icon and tell the NVR you changed the camera password.