travelplus

    My Father lost the TMobile 640 LTE and we bought an ATT  Microsoft 640 Phone and its unlocked. Is it possible to download your Firmware OTA as it recognizes the SIM and i have entered the APN settings and the Microsoft Store allowed me to download the MY Tmobile App.. Can a TMobile Store Flash it to your ROM to Unlock the Band 12 and activate WiFi Calling? Shouldn't WiFI calling be native to Windows 10? I have updated my TMobile 640 to Windows 10 and everything is working except for the WiFI Calling. When will you fix the WiFI Calling.

     

    I am thinking that by linking the phone to  TMobile and adding your ROM should tell the phone to look for your carrier updates and when the new Firmware comes out it should overwrite the ATT firmware and unlock Band 12 and activate WiFI Calling. Please talk with your techs as people bring their own devices and since the ATT Lumia 640 works for TMobile then TMobile should unlock Band 12 and activate WiFI Calling to be fully functional on your network. As there was no TMo phones that I could see online that were new I believe you should be able to overwrite the Firmware when it checks for updates . As the Network Name shows TMoile and I deleted all the ATT Apps shouldn't the phone now look for TMobile Updates for Windows 10 and FIrmware?

     

    I thought by unlocking the phone it debrands the phone from ATT and allows it  to unlock Band 12 and WiFI Calling on the next Firmware Update just like on my Windows PC I can unlock features by updating to Windows 10. Could someone help me to Unlock Band 12 and add WiFI Calling?  I don't want to brick my phone. I am very comfortable with installing the new Windows 10 software but other than that I don't want to Flash it myself.


    Could someone at  a store help me Flash It. I own the phone outright and it should be my right to unlock Band 12 and get WiFI Calling. You allow us to bring our own phones so to make it compatible there should be an easy OTA Firmware download that we can do in your App Store or at your store connecting it up to the machine.

     

    Thanks

      All replies

      • smplyunprdctble

        Installing a custom OS (e.g. not the OS packaged on the phone -- e.g. installing T-Mobile OS on ATT phone) is outside the scope of these forums.  So, instructions, if they exist, wont' be supplied.

         

        However, I can provide some answers to your questions:

         

        T-Mobile Store cannot flash a ROM (again, not supported by any carrier)

        Installing a T-Mobile ROM possibly would enable WiFi Calling (not guaranteed, but there are folks in the Android world who have succeeded with flashing a T-Mo ROM on an ATT phone)

        Band 12 first requires the device to support Band 12.  I don't know if the ATT model does.  Hypothetically, if it did, it should be enabled (unless ATT did something weird to their Radio).  According to GSMArena, only the T-Mobile variant has Band 12: http://www.gsmarena.com/microsoft_lumia_640_lte-7055.php

         

        Installing a carrier's SIM doesn't automatically bring all that carrier's stuff over.  It does to minor aspects with iPhones and certain aspects of Nexus devices, but those are just minor things that Apple and Google have worked with the carriers on getting built in to the phone.  I don't know if Microsoft has done similar yet.

         

        WiFi Calling with Win 10, I can't say anything to that.  I know there's been several conversations on the boards here.

         

        Unlocking a phone doesn't debrand.  It just allows for another carrier's SIM to be used.  Think of it this way -- if you have an unlocked T-Mobile phone and go to England for a couple months, you wouldn't want your phone to "rebrand" itself to Orange (or whatever an English carrier is), then "re-rebrand" itself back to T-Mobile upon your return.  That's a lot of work.

        • leicam

          Re: Unlocked ATT 6M40 Phone unlcoking Band 12.

          As far as hardware is concerned, there is virtually no difference between an AT&T 640 and a T-Mobile 640 (except the back cover). An AT&T branded Lumia 640 can be completely "transformed" into a T-mobile Lumia 640 along with band 12 support as well as Wifi calling (in Windows 8.1) support - but I believe discussing the "how to" violates T&C of this forum. However, I can confirm you the following:

           

          1. You can't put T-mo 640 ROM in an AT&T 640 without first "debranding".

          2. Flashing T-mo ROM doesn't automatically activate band 12 on the "re-branded" phone (the radio part of the firmware needs to be re-initialized).

          3. Wi-Fi calling works just like it does on a T-Mo 640 in Windows 8.1

           

          As smplyunprdctble has already pointed out, Tmo won't "flash" ROMs at the store (or anywhere, really). Also, SIM unlocking doesn't change the firmware.


          Other points you made:

          "I own the phone outright and it should be my right to unlock Band 12 and get WiFI Calling"

          It's still your right - no one is saying you can't. But you can't expect/demand that TMo/someone do it for you.


          "You allow us to bring our own phones so to make it compatible there should be an easy OTA Firmware download that we can do in your App Store or at your store connecting it up to the machine."

          This made me chuckle. Are you saying TMo should have their own version of firmware for every phone that is compatible with TMo's network?

            • smplyunprdctble

              leicam wrote:

               

              "You allow us to bring our own phones so to make it compatible there should be an easy OTA Firmware download that we can do in your App Store or at your store connecting it up to the machine."

              This made me chuckle. Are you saying TMo should have their own version of firmware for every phone that is compatible with TMo's network?

              My "answer" would be "there shouldn't be carrier-specific ROMs".  There's MANY countries that use cell phones and the US are the primary (only?) culprit for customizing ROMs to be carrier specific (noteworthy is the fact you can buy "International Unlocked" variants that don't have all these customizations."

               

              The pro-side of it is you can push OS updates significantly easier (think Nexus and iPhone).  The con side of it is it gives carriers less flexibility when it comes to setting themselves apart (T-Mobile's in-flight texting, WiFi Calling).

               

              But, your snarkiness is approved   Folks generally don't realize that the same "device" on different networks is actually quite different with the innerds.

                • leicam

                  Re: Unlocked ATT 6M40 Phone unlcoking Band 12.

                  My post was in response to "travelplus" who said this: "You allow us to bring our own phones so to make it compatible there should be an easy OTA Firmware download that we can do in your App Store or at your store connecting it up to the machine", which is vastly different than your "there shouldn't be any carrier-specific rom" proposition.


                  But regardless, you have already pointed out the plus side of carrier-specific roms, which is flexibility when it comes to setting themselves apart (T-Mobile's in-flight texting, WiFi Calling).


                  And you have also addressed the unlocked vs carrier-specific issue, which is, you CAN buy unlocked phones and use it on T-Mo - T-Mo allows it. Not sure where the issue is.


                  About my comment being "snarky", let's just stick to the topic instead.

              • ulyssesghost

                You could try visiting XDA Forums and searching it there.  There are instructions.  Not for the feint of heart but it is doable.