Hello, I'm completely new here.

The situation is thus: 2 weeks ago I bought the Deco E3 from Office Depot. It set up with no problems. After a few days I realized that I needed another extender, so I bought the AC1200 aka RE300. Using the Deco app, I couldn't get the extender to work. I tried resetting it several times, moving it around the house, and also completely resetting the network.

I ended up calling tech support. They linked me to tp-link repeater. Net and I was able to configure the extender. But the extender was now (name)_EXT on the network, and for family members would need both the name and the new password, which renders the whole "mesh" concept moot. Also the new range extender doesn't show up in the app with the router and the other extender.  I'd like for the new extender to mesh with the router, as the original one did. IMO all extenders should show up in the same place in the app if they are extenders. 

One thing I tried was downloading TPLink Tether, but even after I tried merging the SSID's, the Extender isn't showing up in the right place on my app (with the other extender and the router). The easy set up was one of the reasons I purchased this system, because I'm not a software engineer by any stretch of the imagination.

Any help appreciated!