When I got back from the store, just in case, I pressed the button on theGREET, and it worked fine with the original 10VAC transformer. I waited a few minutes, and tried again. Worked flawlessly. I tried it several more times with the same result; so I decided to leave the 10VAC transformer, and return the 36VACtransformer to the store it was a lot bulkier than the original one, anyway. The following weekend, I travelled to China,and used the greet to answer my door, and to communicate with my wife and kids, whenever they were at the door. The devicehas been working flawlessly ever since. I have had only one issue, not with the GREET, but with the BEAM wifi repeater. Itlast week went green, and would read as disconnected on the Zmodo app; however, it worked fine as a repeater. I disconnectedit, reset it to factory default, and added it back to the Zmodo App. It is currently working fine. November 1, 2016Hands down for $80 you are not going to find a better doorbell system and Wi Fi extender.