If you have a zte z812 "smartphone" and you want to root it so you can get rid of the ATT bloatware it came with, forget about using dr.fone's marvelous software snakeoil cause it will just boot the phone about 2 dozen times and finally tell you that it doesn't know how to root it.
And while on the subject of this so-called bloat-ware smart AT&T branded go-phone from ZTE. There appears to be no known way to remove any of the "included" software or to root the phone to try and shovel some of the useless crap out of there. Both AT&T and ZTE are equally mum about how to go about trying to salvage any real use out of this terrible product. I managed to get AT&T to give me what they say is an unlock code and it appeared to work to allow me to establish a Ting GSM card account through the phone.
Unfortunately, the best you can do is to "Disable" as much of the useless bloatware nonsense that AT&T bundled into the very limited 8GB sim card it comes with. Here are some screen shots of what I was able to successfully disable via settings/apps route in android....
I installed and finally got it to recognize and mount a 32GB sd expansion card. With the help of the free link2SD android app I've been able to eek out 1.5GB free on the original sim card storage. I placed 12GB of mp3 files on the expansion to enjoy my music via BT headphones while I work etc. Nobody at xda-developers.com has been able to crack this nut though many have tried apparently in the last 30 months or so. I guess I will live with it for a while and see if it is tolerable or not... More on that later perhaps... Or not