[Snap. +] Guide for Flashing Standard FW, Carrier Switching, and Flashing Unlocked FW

[AxlxA]

Yes, that's what I mean by standard firmware (sorry, if I confused you). Your CSC code is already set to "ATT", correct? If not, follow the "Carrier Switching" section and then the "Flashing Standard Firmware" section. If your CSC code is alrready set to "ATT", then just proceed with the "Flashing Standard Firmware" section.

That makes sense. Too bad I can't find the SM-G955A firmware. not even on sammobile.

 

[Mike15678]

That makes sense. Too bad I can't find the SM-G955A firmware. not even on sammobile.

The model number for the firmware is "SM-G955U". The CSC is "ATT". Here's a link to the firmware: http://updato.com/firmware-archive-select-model?record=EF1356CA26EE11E7963AFA163EE8F90B.

 

[AxlxA]

The model number for the firmware is "SM-G955U". The CSC is "ATT". Here's a link to the firmware: http://updato.com/firmware-archive-select-model?record=EF1356CA26EE11E7963AFA163EE8F90B.

Awesome!
my device is being delivered today. I'm just doing all the relevant research to make it work on AT&T. Probably the CSC code is on unlocked until I turn the phone on with my at&t sim and use it a bit.

I'm assuming whenever I do any of these steps, the device gets wiped? So i dont need to worry about setting up the phone/saving files since it's new.

 

[Mike15678]

Awesome!
my device is being delivered today. I'm just doing all the relevant research to make it work on AT&T. Probably the CSC code is on unlocked until I turn the phone on with my at&t sim and use it a bit.

I'm assuming whenever I do any of these steps, the device gets wiped? So i dont need to worry about setting up the phone/saving files since it's new.

Yes, your phone gets wiped, therefore you don't have to complete the setup.

 

[thecrunked]

I'll chime in on Pros/Cons for flashing a stock AT&T S8+ to the Unlocked firmware

Pros:
No Carrier Bloat
Caller ID
Spam Protection
Better Battery Life
More System Storage Space

Cons:
No VoLTE
No Wifi Calling
No Video Calling
No Visual Voicemail built into the dialer app (but if you get the at&t visual voicemail app, it works just fine)

My take:
I switched to unlocked firmware last week and I'm happy so far. I don't really care about volte or wifi calling, maybe your situation is different. I get a lot of robo calls (like 3+ a day) so the caller id and spam protection is a godsend. Also I hate at&t and seeing their logo when i boot my phone and all of their stupid buggy garbage apps i can't get rid of in my app drawer slightly raises my blood pressure every single time i look at them.

Other things to consider
-typically at&t takes extremely long (in relation to other carriers/unlocked) to push out updates, too early to tell how that will play out though
-flashing is not permanent and does not void your warranty, the only negative is that you have to wipe your phone and re set it up and customize things the way you like it

 

[Sheon849]

Finally a guide that works!!! went from Sprint too ATT software with no issues everythinng works.

Sprint software on att was giving me annoying issues with + showing infront of numbers when people call me.

 

[SemperSyd]

Unlocked s8+ to VZW

Sorry if this is dumb, I have an unlocked s8+ from bestbuy (g955u1) , I want to have all verizons features on my phone, should I install the firmware for a g955u? on updato there's one with the product code of LRA but on Sam's there's one with the VZW product code? what's the difference and which would be right to get all the verizon features? Thanks for any advice!

 

[AxlxA]

I got my phone. I am gonna flash the AT&T rom onto the 955U1 unlocked phone. In odin, I am unable to select UMS for the userdata... is that okay? Can I Flash att rom without the UMS?

Update: Bit the bullet. It worked without the UMS. So like mike said, the phone when first powered on with AT&T sim automatically set CSC code to AT&T. So once I figured that out, I just went with flashing Standard Firmware instructions and it worked smoothly. Now i got all the AT&T bloat back but I ALSO GET WIFI CALLING! I work in zero reception some times and I need that wifi calling feature.

 

[SemperSyd]

?

I got my phone. I am gonna flash the AT&T rom onto the 955U1 unlocked phone. In odin, I am unable to select UMS for the userdata... is that okay? Can I Flash att rom without the UMS?

Update: Bit the bullet. It worked without the UMS. So like mike said, the phone when first powered on with AT&T sim automatically set CSC code to AT&T. So once I figured that out, I just went with flashing Standard Firmware instructions and it worked smoothly. Now i got all the AT&T bloat back but I ALSO GET WIFI CALLING! I work in zero reception some times and I need that wifi calling feature.

Did you install a 955U version then? I was unaware that there was any carrier specific versions for the 955U1? Was thinking this may answer my question, I need the use of VZW wifi calling too in my area. Thanks!

 

[AxlxA]

Did you install a 955U version then? I was unaware that there was any carrier specific versions for the 955U1? Was thinking this may answer my question, I need the use of VZW wifi calling too in my area. Thanks!

The U1 phone came with 955U1 firmware(unlocked). It didn't work with any of the AT&T features like wifi calling, VoLTE, Video calling(i've never gotten this to work even on my legit S7edge AT&T variant).

So I installed the rom that mike linked to... which is 955U AT&T version.

For your VZW -
http://updato.com/firmware-archive-select-model?record=090F4262517211E7963AFA163EE8F90B (june update)
http://updato.com/firmware-archive-select-model?record=BFBEC928390911E7963AFA163EE8F90B (may update)
http://updato.com/firmware-archive-select-model?record=4AC3AD4726D511E7963AFA163EE8F90B (April initial release)

I think one of the update takes away bixby remapping function or something... just off top of my head.

 

[Mike15678]

I'll chime in on Pros/Cons for flashing a stock AT&T S8+ to the Unlocked firmware

Pros:
No Carrier Bloat
Caller ID
Spam Protection
Better Battery Life
More System Storage Space

Cons:
No VoLTE
No Wifi Calling
No Video Calling
No Visual Voicemail built into the dialer app (but if you get the at&t visual voicemail app, it works just fine)

My take:
I switched to unlocked firmware last week and I'm happy so far. I don't really care about volte or wifi calling, maybe your situation is different. I get a lot of robo calls (like 3+ a day) so the caller id and spam protection is a godsend. Also I hate at&t and seeing their logo when i boot my phone and all of their stupid buggy garbage apps i can't get rid of in my app drawer slightly raises my blood pressure every single time i look at them.

Other things to consider
-typically at&t takes extremely long (in relation to other carriers/unlocked) to push out updates, too early to tell how that will play out though
-flashing is not permanent and does not void your warranty, the only negative is that you have to wipe your phone and re set it up and customize things the way you like it

Thanks for your input, I'll shout you out.

 

[Mike15678]

Sorry if this is dumb, I have an unlocked s8+ from bestbuy (g955u1) , I want to have all verizons features on my phone, should I install the firmware for a g955u? on updato there's one with the product code of LRA but on Sam's there's one with the VZW product code? what's the difference and which would be right to get all the verizon features? Thanks for any advice!

Use the one that is "VZW". Not the one that is "LRA".

 

[Sheon849]

I went with the unlocked firmware and it's a hell of a lot better.
Is this the most recent unlocked software update? Will we still get OTA updates?

I did notice even after flashing the stock firmware my phone still try to download some Sprint crap even though I unlocked it and am using ATT now. But I blocked it with package disabled pro.

Even though it was trying to download something with Spint ODAM it failed.

 

[Mike15678]

I went with the unlocked firmware and it's a hell of a lot better.
Is this the most recent unlocked software update? Will we still get OTA updates?

I did notice even after flashing the stock firmware my phone still try to download some Sprint crap even though I unlocked it and am using ATT now. But I blocked it with package disabled pro.

Even though it was trying to download something with Spint ODAM it failed.

If you flashed the unlocked firmware that was released on June 12, you should be running the latest. And yes, you'll continue receiving OTA updates, until Samsung ends support for the S8 and S8+.

 

[Mike15678]

I went with the unlocked firmware and it's a hell of a lot better.
Is this the most recent unlocked software update? Will we still get OTA updates?

I did notice even after flashing the stock firmware my phone still try to download some Sprint crap even though I unlocked it and am using ATT now. But I blocked it with package disabled pro.

Even though it was trying to download something with Spint ODAM it failed.

Did you first change your CSC by following the "Changing Carriers" section? You could have changed the CSC to "ATT" or "XAA".

 

[Sheon849]

If you flashed the unlocked firmware that was released on June 12, you should be running the latest. And yes, you'll continue receiving OTA updates, until Samsung ends support for the S8 and S8+.

I am on G955U1UEU1AQE3

Thanks for your awesome guide too.

 

[Mike15678]

I am on G955U1UEU1AQE3

Thanks for your awesome guide too.

No problem.

 

[Sheon849]

Did you first change your CSC by following the "Changing Carriers" section? You could have changed the CSC to "ATT" or "XAA".

No I didn't do that at first I did try the att rom but I didn't like it so I flashed unlocked rom. It's working perfectly fine now. I think the carrier is still set to sprint though. I wonder if I'll have any benefit to getting ATT.

When I flashed your ATT rom it didn't seem to get all the ATT apps. I didn't even get a att boot logo. And it only gave me 1 ATT app.

 

[Mike15678]

I got my phone. I am gonna flash the AT&T rom onto the 955U1 unlocked phone. In odin, I am unable to select UMS for the userdata... is that okay? Can I Flash att rom without the UMS?

Update: Bit the bullet. It worked without the UMS. So like mike said, the phone when first powered on with AT&T sim automatically set CSC code to AT&T. So once I figured that out, I just went with flashing Standard Firmware instructions and it worked smoothly. Now i got all the AT&T bloat back but I ALSO GET WIFI CALLING! I work in zero reception some times and I need that wifi calling feature.

There is a "USERDATA" file in the AT&T firmware. You have to follow the "Prerequisites for Anything You Decide to do in this guide" section in order to make the "UMS" box appear. You flashed incorrectly if you didn't include the "USERDATA" file.

 

[Mike15678]

No I didn't do that at first I did try the att rom but I didn't like it so I flashed unlocked rom. It's working perfectly fine now. I think the carrier is still set to sprint though. I wonder if I'll have any benefit to getting ATT.

When I flashed your ATT rom it didn't seem to get all the ATT apps. I didn't even get a att boot logo. And it only gave me 1 ATT app.

Did you flash the "USERDATA" file in addition to the other ones that were required?