Force device to update carrier settings SM-G781U

Search This thread

tbrou6229

Member
Jul 6, 2022
6
1
Hello, I'm not a developer; I've never dealt with a rooted device, but Google, Samsung, Verizon and other sources were no help, so I'm here now.

I got a Samsung S20 FE from my old workplace which was previously locked to the ATT network. I am a Verizon customer so I wanted to switch over and I purchased an unlock code from cellunlocker.net. I've reached out to Cellunlocke, but they say the unlock was successful as it is connecting to the VZW network.

I did a factory reset on the phone, put in the Verizon Sim card, and used the network unlock code provided. The unlock said it was successful, but the phone powered on with the ATT logo and downloaded all the ATT factory apps. When I go into the phone dialer settings, it shows ATT video calling, etc... The phone software version shows ATT in the service provider sw version. But it makes calls, texts, etc. and the network settings show it's connected to VZW. The problem is, that it can't access my voicemail or use wifi calling because it's set with the ATT apps and features.

I've tried removing the sim, power cycling, factory resetting, even calling Verizon and asking them to resync the phone to the network. When the sim card is installed in the new phone, VZW shows the S20 as my device, but the phone still thinks it is on the ATT settings. I've viewed the Service Menu *#0011# and it shows that the phone is unlocked.

The phone is showing a service provider software version of
SAOMC_SM-G781U_OYN_ATT_12_0012
ATT/ATT/ATT

Is there any way to force the phone to reset its carrier settings or service provider software? Also, please keep it somewhat simple; I'm learning but not an expert here!
 

3mel

Senior Member
Aug 23, 2012
1,700
548
London
about the only wise thing you can do is download and XAA U1 firmware (Samsung non carrier firmware) flash that with Odin and call it good.

you're getting what you're seeing because the phone won't be able to switch to Verizon firmware as Verizon actually have their own unique version of the FE SM-G781V I believe with physical differences for Verizon's mmwave 5G and the U model can't reset itself to that.
 

tbrou6229

Member
Jul 6, 2022
6
1
about the only wise thing you can do is download and XAA U1 firmware (Samsung non carrier firmware) flash that with Odin and call it good.

you're getting what you're seeing because the phone won't be able to switch to Verizon firmware as Verizon actually have their own unique version of the FE SM-G781V I believe with physical differences for Verizon's mmwave 5G and the U model can't reset itself to that.
So which firmware version do I need? The model printed on the phone is SM-G781u. SamMobile has 781O, B, U, U1, and V for the 781 model.

I'd love to have it without the bloatware Verizon installs, but I need Wifi calling to work and it seems to be a setting in the dialer, rather than the phone.
 

3mel

Senior Member
Aug 23, 2012
1,700
548
London
So which firmware version do I need? The model printed on the phone is SM-G781u. SamMobile has 781O, B, U, U1, and V for the 781 model.

I'd love to have it without the bloatware Verizon installs, but I need Wifi calling to work and it seems to be a setting in the dialer, rather than the phone.
flashing V would be a bad idea, 5G wouldn't work, at least not well. so that leaves U1 which is Samsung unbranded, no carrier apps at all.
 

tbrou6229

Member
Jul 6, 2022
6
1
flashing V would be a bad idea, 5G wouldn't work, at least not well. so that leaves U1 which is Samsung unbranded, no carrier apps at all.
I'm looking at the instructions for flashing the device and the instructions say to turn on OEM Unlocking in developer options. I've activated developer options and USB debugging, but do not have the option to turn on OEM Unlocking.

I can't seem to find a way to unlock the bootloader.
 

3mel

Senior Member
Aug 23, 2012
1,700
548
London
I'm looking at the instructions for flashing the device and the instructions say to turn on OEM Unlocking in developer options. I've activated developer options and USB debugging, but do not have the option to turn on OEM Unlocking.

I can't seem to find a way to unlock the bootloader.
to the best of my knowledge you don't need to be unlocked in order to flash signed, official Samsung firmware. many Americans have cross-flashed their phones and none of them could unlock either.

you're just booting into download and opening Odin, it's not much more than that.
 

tbrou6229

Member
Jul 6, 2022
6
1
to the best of my knowledge you don't need to be unlocked in order to flash signed, official Samsung firmware. many Americans have cross-flashed their phones and none of them could unlock either.

you're just booting into download and opening Odin, it's not much more than that.
Awesome, a flash using ODIN seems to have worked; the phone is active and not showing any carrier apps or splash screen. I'm having some other issues; can you suggest which firmware combo would be best?

I used Sammobile.com SM-G781U1 with Country Code USA (Verizon) (VZW)
OR I also downloaded Frija SM-G781U1 with CSC of XAA

Will I notice any major differences in them, or just try each one and check it out?

I am in the US, using the Verizon network. We do not have 5g in the area but the phone and our verizon plan is 5G capable and I would like the option if it exists somewhere I travel to.
 

3mel

Senior Member
Aug 23, 2012
1,700
548
London
I am in the UK, I shouldn't be telling you anything about what firmware is gonna be best over there.
other than U1 XAA I can't tell you much. also be aware that generally you can never downgrade your firmware unless it has the same bootloader version as what you're currently using...
if we were looking at my firmware version number G781BXXU4FVE6
I can only flash something that has a matching 5th last character, that's a 4 in this case. I can only download and flash older firmware if it also has a 4 in the same place in the build number. the phone won't accept anything else.
Sammobile is good for seeing what firmware exists but it's terrible for download speeds. I use Frija mainly but that only gives me the latest version nothing historical.
 

tbrou6229

Member
Jul 6, 2022
6
1
@3mel thank you for all your help! I've got this device working well on the U1 software and didn't have to reflash it; the rest of my issues resolved. Thanks for your patience in helping this newbie do things to a phone I never would have attempted otherwise!
 
  • Like
Reactions: 3mel

Top Liked Posts

  • There are no posts matching your filters.
  • 1
    @3mel thank you for all your help! I've got this device working well on the U1 software and didn't have to reflash it; the rest of my issues resolved. Thanks for your patience in helping this newbie do things to a phone I never would have attempted otherwise!