How do I change the APN setting on my unlocked Verizon HTC One?

[AC Question]

Unlocked verizon htc one issues!

I got my htc one m7 unlocked from verizon to tmobile and i am pissed of due to 2 many issues. 1. i can not change the apn settings. I get the freaking E with the arrow which is absolute garbage data, takes like 3 minutes to open a google search. And 2. I can NOT receive any group txts or any pictures. When i do, it asks me to download them but it says generic download failure or something along those lines. Can someone please help me! This issue is frustrating me.
HTC6500LVW
ANDROID 4.4.3

is there anyway i can change the apn either by flashing to a older version like 4.4.2 or lower if there is or root it and change the apn manually

 

[Rukbat]

Re: Unlocked verizon htc one issues!

No, no and no. Unlocking only guarantees that the phone won't reject a foreign SIM, it doesn't guarantee that the phone will run on another network. If it doesn't have radios for the bands your new carrier has, it just won't work any faster than EDGE.