Can't connect Google Mini to T-Mobile Home Internet

Stjon wrote:

I've tried every recommendation in the book restarting the "T-Mobile" device, the mini. It will go through the entire process of adding the device and at the very end, after it's verified the connection, it suddenly says it can't connect to the network and fails the addition.

So, I had the same problem, but here is how I got it to work. I RESET all my google minis to factory reset. Then I erased ALL of my homes. I started from scratch with all a new home and devices on my network. Then it worked like a charm.