A LOT of T-Mobile ID issues as a Home Internet customer

As only a home internet customer (signed up/activated in store and now equipment in my home), I experienced the same "don't recognize this email" hurdle as mentioned here and in many other forums. I finally had success signing up for the ID via the "T Life" app on my phone. It produced a very similar sign up page as the standard app and website, but unlike those others, allowed me to proceed without errors. I'm pretty sure I didn't even capitalize the first letter of my email address on the successful attempt, but you might as well try that as well. Hope this proves successful for everyone else.  My phone was on my T Mobile Home WiFi at the time and the "T Life" app appeared to recognize I was using my new router during the process.