Lumia 640 T-Mobile windows 10

[RumoredNow]

https://support.t-mobile.com/thread/134436?start=0&tstart=0

I use Band 12 with my debranded ATT and flashed to TMO phone running windows 10. The link explains why it works.

Any chance you could write this up as a How To for our forum users? Is it just 640, looks like it would apply to any cross branded Lumia...

 

[boonesmi]

https://support.t-mobile.com/thread/134436?start=0&tstart=0

I use Band 12 with my debranded ATT and flashed to TMO phone running windows 10. The link explains why it works.

neither of the ones i mentioned are rebranded ATT (both original tmo 640's).

and yes i am very familiar with running win10 and ims registration issues. and yes i know that running win10 on tmo network it will "work" on band 12 (my daily driver is tmo 640 on w10m, and it often times uses band 12 and volte (hd voice also shows)

but.. and its a big but (lol, not to be confused with a big butt) its buggy, its not an issue for me and my daily use.

on the other hand if my wife uses the same phone at work (hers has been upgraded twice over the months and downgraded again twice) OR if she borrows my phone (which i had her do for testing purposes after the 2nd time i tried win10 on her phone)

her office is in a location with very weak/non existant signal on any band other then band 12. after awhile (exactly how long i don't know, she is kind enough to do the little testing ive asked, but its very inconvenient for her) but after awhile IMS de-registers at which point both voice and text stop working.

at that point if she walks over near one of the big windows (she is in a huge office building in atlanta area) and if she waits awhile (like at least 5 or 10 min) ims will register again and things will work for a little while.

this link has a very long discussion on the issue ive read thru it a couple times, very deep inside you start getting a lot of detailed info on what exactly is going on (including an actual microsoft engineer who works on the wifi calling team)
http://answers.microsoft.com/en-us/...d/1ea2a4b5-9b2d-46ad-a3ad-e160686766f4?page=1

 

[boonesmi]

https://support.t-mobile.com/thread/134436?start=0&tstart=0

I use Band 12 with my debranded ATT and flashed to TMO phone running windows 10. The link explains why it works.

so i just read through that link. that doesn't appear to be any new info.
the key point is to make sure you update NVI when flashing, but again this is very old info. i really wish the OP of the xda thread would update with that info.

half a dozen times ive seen people complaining about wifi calling or lack of band 12 on a rebranded ATT on TMO network. the first thing i always ask "did you do the full NVI update"? the answer is always either "no" or no answer at all. it would save so many people trouble if that xda OP was updated

lol OR if people would just read. i mean heck it is "the most thanked" post in that entire xda thread (the post that has the all important "-do_full_nvi_update" parameter


edit to add:
both my wife and i use the tmo 640 as a daily driver, both are original tmo version.
but i have bought a bunch of ATT versions since then. a couple for $39 when MS had them on sale, then 5 more on black friday for $29, and then i cleared out all of my local walgreens for another 7 (they ranged from $8 - $14 depending on location)

and no i didn't list them on ebay, lol

i have a big family spread all over the country, and for some reason the vast majority use windows phones, most were on old lumia 521's still, our family fills up two different tmobile family plans, lol. anyway i gave most of them away after flashing them to TMO version. i still have 1 left as a backup, which just recently i stole the battery out of to replace my wifes.

 

[boonesmi]

lol, dang im being long winded, but i was thinking about it after that last post. and i think i see where people could be confused by that post (the one at tmobile support that bob hanson linked)

he talks about his phone being "de-branded" and how you can call tmo and have them register the IMEI. but his phone is technically "re-branded" (at least im assuming this by his statement:

"thor2 -mode uefiflash -ffufile "C:\Lumia\RM-1073\RM1073_02177.00000.15203.26115_RETAIL_prod_si gned_1001_023F70_TMO-US.ffu" -do_full_nvi_update -do_factory_reset"

so the guy clearly turned it into the TMO version. and as countless people can attest to, an ATT rebranded to tmo running win8.1 works great with band 12 and with ims registration and all of the services that can be run over LTE

now if the guy was able to take a factory unlocked or cv variant that would be something impressive that could possible be applied to other phones (ie. lumia 950) i just don't think thats whats going on

 

[Bob Hanson]

All I was trying to point out is that my ATT rebranded to TMO running windows 10 is working fine with band 12 and ims registration (but I never had to call TMobile to get registered). And yes the thor2 with -do_full_nvi_update was key. Wi-fi calling does not work.

 

[boonesmi]

All I was trying to point out is that my ATT rebranded to TMO running windows 10 is working fine with band 12 and ims registration (but I never had to call TMobile to get registered). And yes the thor2 with -do_full_nvi_update was key. Wi-fi calling does not work.

honestly my ramblings were in response to the article you linked, not to yourself.

also i strongly suspect that most people running w10 on tmo 640 don't have a fully functioning phone even though they think they do. its just a case of not being in the conditions that cause the known issue to rear its ugly head.

the thing is that if you are never (or rarely) in that situation, then the end experience of w10 is positive and worth the upgrade over 8.1 (i personally use win10 on my daily driver tmo 640)