Good grief...I now can get 4 of the five to take a new address, I did not do anything different. BUT...when I try to do a read back of the addresses on all of them, I get a different random number back every time and any other CV read back gets me the "d nd" code. I also get the same results now with my Atlas and Kato locos with a mix of Digitrax NCE, and Lenz decoders. The fifth DZ125 decoder still refuses to to anything other than operate on address 03. I can't reset it or do anything with it and have tried it in different locos. I wonder if I have a bad decoder AND a bad zephyr. The zephyr hit the floor about two months ago when we were moving the layout, maybe I broke something.