ADT set up 3yrs ago, did not provide password. when i switched NVRs , all 10 dome style 4220s did not work on new NVR until firmware was updated. 5 of the 5421e IPCs worked without firmware update.. 3 cameras 2 dome 4220s, and 1 5421e, did not and because I put in the wrong login when plugged into new NVR, when I replugged them back into old NVR, they, locked up for password.. So I was able to factory reset the 4220s. but not the 5421e.
I held the two tabs on the right side of the PIC you sent. That didn't work. Still trying to figure which is the button. There is a top ? and bottom USB? beyond the SD slot.