Root root or not?

[shellroc]

Newbie here. I will try to explain/ask questions the best I know how.
I was given a samsung galaxy s3, sgh i535, verizon phone. My carrier is at&t (which was used in a samsung galaxy s3 sgh i747.) As you might guess, I want to use my at&t sim card on the verizon phone....HOWEVER, I cant get it to work. the verizon phone has the option to change the network to at&t.. so I put in the appropriate apn, but it didnt work.. maybe, someone can walk me thru that again, and it will work. Im not sure if this "root" thing is what Im supposed to do. everything I see about "root", is for a sch i747. So, here are my questions: Do I root or not? where do I find "all" the files to put on phone, and do I leave OUT the verizon sim card when working on phone to change to at&t, and when do I insert at&t card. The Odin3 files I've been locating, do not have the PDA option. or I have to download a crap load of other programs just to get it. I'm NOT sure exactly what files I need.. actually, Im not sure what Im doing.. please send me "links" to do the right thing.

 

[Jfalls63]

You can easily root the i535 with Towel Root apk. The i535 is not a good choice to try and use on AT&T network with only 2g being compatible.

 

[shellroc]

the phone says its 4g lte. android 4.4.2 kernel 3.4.0. sorry about above info. it is a sch i535.. not sgh i535, if that makes a difference.

 

[Jfalls63]

Verizon network is CDMA and their phones have different radios for their network. AT&T network is GSM. While the i535 will receive 4glte on Verizon, it will only receive 2g signal on AT&T.

 

[Jfalls63]

There is a YouTube video but I'm having trouble posting a link. It's how to activate a Verizon phone on AT&T.

 

[Jfalls63]

Put in your AT&T Sim.
Go to settings, more,mobile networks,network mode. Change from LTE/CDMA to GSM/UTMS. Then go to APN settings and add settings for AT&T and save.

 

[shellroc]

did that first thing.. but, since you suggested it again, I did it again. it asked if I wanted to switch to global?? also, Phone activation" this sim card is from an unknown source.". so, it didnt work....I used the at&t hspa+.. is that correct?

 

[Jfalls63]

HSPA is 3g and the i535 doesd not have the correct hardware to receive 3g on AT&T network. You should be able to receive EDGE (2g). I have used my i535 with Straight Talk and their Verizon compatible sim which uses Verizon network. Never tried to run it on AT&T,2g internet speed would be to slow for me.
My best advice would be to take it to AT&T store and see if they can get it set up for you. Sorry I couldn't be more helpful.

 

[mikedt]

did that first thing.. but, since you suggested it again, I did it again. it asked if I wanted to switch to global?? also, Phone activation" this sim card is from an unknown source.". so, it didnt work....I used the at&t hspa+.. is that correct?

I know people have had problems like this before with Verizon phones, both here on AF and seen it myself a couple of times when they've come to China. They're supposed to have been unlocked, but they won't accept anything but a Verizon SIM, "Not a Verizon SIM" or something like that. Even if though the phone itself does have the correct bands and modes for wherever it is. I've told them to go back to Verizon about it, as might not have been properly unlocked, or released from contract, or whatever, but that's rather difficult when you're in a foreign country.