yashsingh1/xdaforums huggingface dataset:
[OnePlus 8 Guides, News, & Discussion] RandomPooka:
2 posts above yours, someone answered the version question. It's not terribly difficult to reflash the modem image. There's good instructions on how to do the persist restoration if you need it.

Pretty much all of my questions were just conveniences based, except for the one about version mismatches. That was answered, so the rest is just either trying it and seeing if it works, or doing it the documented way and fixing trouble spots IF they pop up.

Three only one I'm not confident in is removing the -w from flash-all.bat. there's probably notable changes between T-Mobile and global system settings, and carrying over your user data to the global ROM is asking for problems that nobody will help with because you didn't follow instructions ?

I'm probably still going to try it. Worst case is that I'll still need to wipe data after.
[OnePlus 8 Guides, News, & Discussion] masterchiefb117:
Can any verify my work?

T-Mobile IN2017 (Bought a dual SIM tray from Amazon to convert to Dual SIM capable)

TMo 10.5.20 > TMo 10.5.7 > Bootloader Unlock > Global 10.5.12 > OOS11

I had Dual SIMs in the notifications bar, "recognized", but SIM 2 would not activate. (Side note Verizon and Visible SIMs work flawlessly in OOS 11)

In an effort to fix SIM 2 I went back to TMo 10.5.7 and went thru the process again but this time I am only getting 1 SIM 1 read instead of 2.

What I've tried so far is;

TMo 10.5.7 > Bootloader Unlock > Global 10.5.11 (Reads SIM state as 1 & 2)> Update to 10.5.12 (Missing SIM State) > OOS 11

TMo 10.5.7 > Bootloader Unlock > Global 10.5.12 (Reads SIM state as 1 & 2) > OOS 11

TMo 10.5.7 > Bootloader Unlock > Global 10.5.11 > OOS 11

Tmo 10.5.7 > Update to TMo 10.5.20 > Unlock Bootloader > Global 10.5.12 > OOS 11

For some reason, I cannot get the OnePlus 8 to read Dual SIM like before.

I have noticed in reading the CMD lines that when doing;

flash-all.bat 10.5.11 it will flash modem b

flash-all.bat 10.5.12 it will flash modem a

Im wondering if there is an updated config that I need to follow. SIM 2 only reads fine when I have 1 SIM in there so its not a hardware issue.

---------- Post added at 11:29 PM ---------- Previous post was at 11:11 PM ----------

Also to add us after going into OOS 11 sim swapping doesn't seem to be an issue anymore. I have swapped sims like numerous times in the attempt to get Dual SIM working again without the OnePlus 8 totally losing all service like it was in OOS 10.

---------- Post added at 11:29 PM ---------- Previous post was at 11:29 PM ----------

Also to add us after going into OOS 11 sim swapping doesn't seem to be an issue anymore. I have swapped sims like numerous times in the attempt to get Dual SIM working again without the OnePlus 8 totally losing all service like it was in OOS 10.
[OnePlus 8 Guides, News, & Discussion] nlsroot:
So I've just done a successful migration on the first try.

Initial status: IN2017 T-Mobile 10.5.20, SIM unlocked running on Google Fi. Lot of networking issues (can't call or get called).

Actions:

- Restore to T-Mobile 10.5.7 via instantnoodlet_15_O.06_200411

- Go through the wizard, enable Developer options and enable OEM unlocking.

- Reboot to fastboot

- Running fastboot flash cust-unlock unlock_code.bin

- Running fastboot oem unlock

Then downloading the latest global FASTBOOT ROM on the Sourceforge repo.

The last thing was to unzip the ROM (10.5.12-GLOBAL-OnePlus8Oxygen_15.O.21_OTA_021_all_2008080054_906daa239-FASTBOOT in my case) and run the flash_all utility in it. The phone restarted and I went through the classic setup. No networking issue for the last hour...

You can't relock the bootloader directly. You end up with a corrupt warning. Flashing 10.5.1, doing the full OTA update via OxygenOS, rebooting and relocking worked :)
[OnePlus 8 Guides, News, & Discussion] sx10:
I'm still getting no cell info for 5g. This is on the stable OOS11 Global, OP8 on T-Mobile. I have heard from two people now that they are seeing the 5g cell ids on the OP8 or Pro, but I can't get it to work. I do have the R15 SIM.

Backing up a little, my goal is to start mapping the 5G towers with Cellmapper. Android 11 is supposed to report the 5g cell data to cellmapper and other apps. On the tmobile branded rom (Android 10) 5g works in NSA and SA but neither report cell id. On the OOS11 Global Rom NSA works, SA does not, and there is still no cell id. I tried flashing the tmobile modem to OOS11 but it didn't like that one bit. Anyone have any insights on this? Thanks.
[OnePlus 8 Guides, News, & Discussion] erik29gamer:
Just want to confirm, I was also successful doing exactly this. Not using Google Fi, but was still having network issues with T-Mobile.

It's only been ~24 hours, but haven't noticed the problems I was previously having consistently.
[OnePlus 8 Guides, News, & Discussion] crazynapkinman:
Do you think i have to be on Tmo 10.5.7?

Could I just fastboot flash the rom since I'm rooted on Tmo 10.5.21?

I have xXx installed but can easily remove the module to revert to stock rooted 10.5.21
[OnePlus 8 Guides, News, & Discussion] bluemoel:
After allowing the global to update itself with the global modem, I did a speed check. The down load is the same but upload isn't going more the 1 mbs... I was going to try and flash the T-Mobile modem back again using twrp. But after doing the local upgrade twrp isn't recogniZing any partitions to restore in the backup. Does this have something do with the a/b thing and not being in the same slot? I've tried booting into both slots and neither of them pick up the backed up partition ....
[OnePlus 8 Guides, News, & Discussion] gerguter:
I am updating now, although when I flashed the 10.5.7 I had signal with the Global version. Either way, thanks alot for you work on this and putting this guide together!
[OnePlus 8 Guides, News, & Discussion] rjp0615:
*cough* PATCHED MSM TOOL *cough*
[OnePlus 8 Guides, News, & Discussion] Some_Ghost:
it's not as easy as you think, OnePlus has made it more difficult
[OnePlus 8 Guides, News, & Discussion] Inversity:
I'm unable to get signal even after I restored my backed up modem. I'm stuck right now
[OnePlus 8 Guides, News, & Discussion] Vio281:
better request a replacement and hope they dont find out you did anything.
[OnePlus 8 Guides, News, & Discussion] gerguter:
https://xdaforums.com/oneplus-8/how-to/op8-unbrick-tool-to-restore-device-to-t4085877

Follow this guide. It will get you back to stock and you'll be good to go.

Alternatively, root and then use Oxygen Updater from the Play Store to update and that should take care of your modem issues.
[OnePlus 8 Guides, News, & Discussion] ecompton59:
the first 5 are on 5g only the fast one i switched to 4g ive been thinking that TMobile 5g isn't very good yet i had 33% reliably on network i ran for 24hrs on 4g my speeds are faster then the lg g6 unroted it gets max 20mbs my area sucks i think its OnePlus and TMobiles falut not the rom and under internet settings v2 it doesn't even have 5g selection
[OnePlus 8 Guides, News, & Discussion] ecompton59:
big question is does anyone have a T-Mobile modem from twrp or img file
[OnePlus 8 Guides, News, & Discussion] free4flight:
What happened to the boot.img you were gonna share?
[OnePlus 8 Guides, News, & Discussion] Vio281:
having 5g doesnt necessarily means faster speed, its better congestion, just like using wifi router connect to the internet between 2.4ghz or 5ghz band.

I live in MD and gotta say during traffic jam, 5g has loaded a lot better than LTE.
[OnePlus 8 Guides, News, & Discussion] ecompton59:
on T-Mobile when i rooted did the little network hack i was 198mbs download 45upload now it takes 4 g to get above 100
[OnePlus 8 Guides, News, & Discussion] 2matos:
do i need to update to global to root my phone?
[OnePlus 8 Guides, News, & Discussion] bluemoel:
https://drive.google.com/folderview?id=151WKuevPJjjRgS8PL0vMt99GraLSxWbI

its been one thing after another.

I used the unbrick tool trying to beabele to get access to the tmo 10.5.8 update so I could upload it. its been failing and I thought it was cause I was rooted and unlocked. nope. I just realized I accidently deleted my reserve.img!!! ****. could some one please make a copy of their /data/reserve/reserve.img and upload it. I wasted nearly a day trying to dumpsys track and all that find the update to upload it, and the whole time it wasn't working it was actually cause I didn't have that img

---------- Post added at 02:28 AM ---------- Previous post was at 02:19 AM ----------

https://www.dropbox.com/s/co9hf4b8vbtmfat/modem.emmc.win?dl=0 is the 10.5.8 updated one

https://drive.google.com/folderview?id=151WKuevPJjjRgS8PL0vMt99GraLSxWbI the modem there is stock out of box
[OnePlus 8 Guides, News, & Discussion] free4flight:
Thanks much appreciated, do you have the 10.5.8 boot.img, patched or not? I am on 10.5.8 OS...tia
[OnePlus 8 Guides, News, & Discussion] ecompton59:
thank you man im going to see if it fixes issue and pull it for others. it booted with twrp test10 testing
[OnePlus 8 Guides, News, & Discussion] ecompton59:
the 40 mbps is global modem i switched system_a & system_b
[OnePlus 8 Guides, News, & Discussion] nlsroot:
I think it depends if you want to relock the bootloader or not. From what I've experienced, you can only relock after a full OTA update. Everything else I've tried failed and ended up in a corrupt stance. So yes I think you need to force a downgrade before reupgrading everything.

Btw, it has been 24h and for the first time in 3 months, I can now get phone calls. How amazing is that :p
[OnePlus 8 Guides, News, & Discussion] crazynapkinman:
Can anyone verify if downgrade is necessary to convert to global?
[OnePlus 8 Guides, News, & Discussion] sx10:
You don't need to downgrade. Just unlock and flash-all the fastboot rom.
[OnePlus 8 Guides, News, & Discussion] RandomPooka:
I can verify that it works with the 20 build. I don't know that 21 changed enough to break it. Agree that you should be fine to just go for it
[OnePlus 8 Guides, News, & Discussion] crazynapkinman:
So to clarify:

I am rooted with xXx magisk rom mod.

I would take the following steps:

Reboot to fastboot.

Extract all files from fastboot rom zip (downloaded global A11 rom)

Plug phone in whole in fastboot bad use:

fastboot flash flash-all.bat (from extracted files of global rom)

Reboot.

Complete setup (skip what I can to get to booted)

Developer Options

Enable oem unlock and ADB

Reboot to fastboot

Oem unlock

Fastboot boot twrp

Backup boot partition

Boot phone

Patch boot with magisk

Move patched_magisk to pc

Reboot to fastboot

Fastboot boot patched_magisk.img

Once booted, open magisk bad direct install

Reboot.

Once booted, install xXx mod?

That process sound correct and flawless?
[OnePlus 8 Guides, News, & Discussion] sx10:
I don't believe anyone has posted a fastboot flashable A11 stable yet. The latest is the Global 10.5.12. You can convert to it and then OTA to A11. Then you can flash a patched boot to get root back. So it's even simpler than you have there...

Make sure you are unlocked, which it sounds like you are since you rooted.

Extract all files from fastboot rom zip (from https://sourceforge.net/projects/fastbootroms/files/OnePlus 8/)

Reboot to fastboot

Run flash-all.bat

A bunch of stuff will flash and phone will reboot twice

Complete setup (skip what I can to get to booted)

You are now on Global Rom and can upgrade to A11 with local upgrade or oxygen updater

To get root back, get patched boot for whatever version (from https://xdaforums.com/oneplus-8/how-to/guide-magisk-oxygenos-11-beta-1-global-t4160833)

Install Magisk Manager

Reboot to fastboot

fastboot flash boot patched_boot.img

Reboot
[OnePlus 8 Guides, News, & Discussion] mslezak:
I'm curious if you can relock the bootloader after updating to 11 stable. I was running a modded 11 OOS BluSpark kernel and Magisk 21.0 a few days ago but messed with a system file, now msm back on crap T-Mobile software. I swear Global 11 modem works better than T-Mobile's. Still get 5g. Beware stable 11 changes button combos for fastboot / EDL and the only TWRP can't mount data. Beware! It's quite difficult to fix any errors. Only EXKM would flash BluSpark. Just saying I build kernels and am pretty technical and it was still a huge pain for me to unbrick it.
[OnePlus 8 Guides, News, & Discussion] RandomPooka:
What are the new button combos? And I didn't think TWRP would even boot on 11
[OnePlus 8 Guides, News, & Discussion] sx10:
I agree the Global modem is pretty fast, but it doesn't support 5G SA like the Tmobile modem. I tried flashing the tmobile modem on the new Global 11 and it just bootlooped. Could be that I messed up the flash because it had to do it in fastboot instead of twrp. Has anyone else gotten that to work?
[OnePlus 8 Guides, News, & Discussion] crazynapkinman:
I have just finished flashing the flash-all.bat....

After updating, my sim shows two connections? one "3g" and one "r" Is that normal for global rom? it also says 31000 instead of sprint. also, no wifi calling...

---------- Post added at 11:16 PM ---------- Previous post was at 10:58 PM ----------

When you switched to global, did your data/cell signal notification change to "3g" and "r"?

i am calling and texting fine. but my network says "31000" and my icons are looking different.

EDIT/UPDATE:

So after fully updating GLOBAL to A11, sprint is working fine. I cannot seem to gain root by flashing the patched magisk file you provided the link for, however. I've tried downloading the patched version, and patching it again via magisk.. I"ll try the stock version and patch it as well, see if it works.
[OnePlus 8 Guides, News, & Discussion] RandomPooka:
I had to download the stock boot.img and patch it myself. Couldn't find a pre-patched image that worked. Definitely glad that we can fastboot boot images, and aren't stuck using flash only. That would have been tedious, since I didn't have the stock boot image when I started and don't have them pc set up for pulling it from the payload.bin
[OnePlus 8 Guides, News, & Discussion] crazynapkinman:
I got it working by flashing boot_a and boot_b with patched_magisk.img

Seems simply flashing one slot isn't good enough to stick root.
[OnePlus 8 Guides, News, & Discussion] aoe2exp:
Will this allow me to turn an IN2017 to use dual SIM?
[OnePlus 8 Guides, News, & Discussion] erik29gamer:
I see the option for SIM 1 and SIM 2 on mine, and bought the dual sim tray, but don't currently have a second SIM to test functionality. From what I have seen other's say, it works as expected.
[OnePlus 8 Guides, News, & Discussion] shooterx:
Weird. I did:

Unlock bootloader --> twrp & root --> backup persist and modem --> MSM Tmobile 10.5.7 --> unlock bootloader again --> recovery to 10.12 --> upgrade to Android 11. Not seeing any dual sim support at all with two sims inserted. Did I happen to miss something along the way?
[OnePlus 8 Guides, News, & Discussion] mslezak:
There is no 2nd sim slot on the IN2017!

Title says it all. Look I have 2 phones one with dual sim one without. There are no sim connections for a 2nd sim card on the T-mobile OnePlus 8. Shine a light in there you'll see the top doesn't look like the bottom...
[OnePlus 8 Guides, News, & Discussion] shooterx:
Shame on t-mobile. Lesson learned to never buy carrier locked again. I was good with doing that for so many years.
[OnePlus 8 Guides, News, & Discussion] mslezak:
I got Global bootloader locked Android 11 OOS, MINT (T-mobile MVNO) working fine after a few reboots on T-mobile settings.

Just update using system to 11 then relock before it boots for the first time. fastboot flashing lock
[OnePlus 8 Guides, News, & Discussion] xxBrun0xx:
Do you get "no sim" error every few hours? I've been on a converted tmobile oneplus 8 on beta android 11 for a few weeks now, haven't been able to find a solution. Curious if it's just me or if it's a common problem on the converted devices.
[OnePlus 8 Guides, News, & Discussion] crazynapkinman:
Been on tmo converted for a few weeks. Never had this issue you speak of. I'm using a Sprint sim tho. Maybe that makes a difference... Maybe.
[OnePlus 8 Guides, News, & Discussion] mslezak:
Switch to stable 11 with Oxygen Updater (or use the System app, it's way faster download speed). No issues like that at all. If you continue to get the sim disconnecting go to T-mobile and tell them your sim is defective. See if they'll just give you a new one.
[OnePlus 8 Guides, News, & Discussion] xxBrun0xx:
I'd love to, but I'm using an mvno (Mint). Sim worked perfectly with my oneplus 7 pro, as soon as I switched to the OnePlus 8 I had issues (on both TMobile firmware and international android 11). No twrp for A11 yet, but I do have a backup modem from android 10 TMobile
[OnePlus 8 Guides, News, & Discussion] RandomPooka:
The backup modem from 10 has caused failure to boot for others when trying to flash it to 11
[OnePlus 8 Guides, News, & Discussion] freddienuxx:
you think this will work on 8T? I'm dying to unlock it. I'll try anything lol

OP8T
[OnePlus 8 Guides, News, & Discussion] RandomPooka:
You want to attempt to flash a rom that isn't for your device in an attempt to unlock the bootloader?

I would suggest trying reading more, since you said you'll try anything.
[OnePlus 8 Guides, News, & Discussion] mslezak:
Op8 and Android 11 w/ an MVNO

I'm on Mint and Global Android 11 stable BL locked it usually works fine. But Op8 TMO they did something to their Wholesale APN to drop the connection speeds after the Sprint merger. I used to be able to just use the standard fast TMobile APN. But to your point I have another 865 phone that never has issues on TMobile fast APN with Mint. I noticed if you go to Wholesale APN then switch to fast TMobile APN sometimes it does better on the network. If all else fails just reboot. One issue I have seen on Mint (I presume) the phone will go right to VM if it's not properly registered on the network. Or the phone rings and shows someone called but I don't hear ringing - which sounds like a software issue to me.
[OnePlus 8 Guides, News, & Discussion] hyelton:
For Android 11 do we still have to flash the T-Mobile modem or does it just work?

Also do we have to have an unlocked bootloader to just switch to global? I dont root. Thanks.
[OnePlus 8 Guides, News, & Discussion] crazynapkinman:
It just works. But no SA 5G.

I'm not sure if you can flash Tmo modem from a10 over a11 global modem.

It's be nice to know since SA is pretty dang nice.
[OnePlus 8 Guides, News, & Discussion] hyelton:
Thanks! Can it be flashed without unlocking the bootloader? since apparently I have to wait up to 7 days for that.

I thought SA just worked with Android 11? Does forcing NR only work? Only reason I like SA is it seems easier to force lowband 5G when needed for hotspot for those times internet is out. Lowband 5G is a lot faster than LTE here.
[OnePlus 8 Guides, News, & Discussion] crazynapkinman:
You need BL unlock to flash anything rom related.
[OnePlus 8 Guides, News, & Discussion] hyelton:
I don't care about custom roms. Just stock firmware no root etc.

Seems like the 7t doesn't require a bootloader unlock for stock firmwares.
[OnePlus 8 Guides, News, & Discussion] mslezak:
Yes you unlock and relock BL for 11, no modem required

The A11 modem is already updated for TMO in fact I think it's more updated than T-Mobiles version on 10. I haven't checked EFS explorer (QFIL) to verify (Qualcomm tool).

You can't move to A11 now without unlocking the BL, converting to Global, taking the A11 full update, then relocking the BL. T-Mobile is supposed to have a beta anyway they are testing should come year end 2020 or Jan 2021 if you just wait.

Of course updates will be slow... I got an A11 update in a week on Global. Not happening on TMO.
[OnePlus 8 Guides, News, & Discussion] hyelton:
Thanks.

Won't be so bad at the end of the week as the OP8 won't be the main device anymore.

But non working calls at random times. And text message delays until I pick up the phone, or texts not sending etc etc have made this phone useless on T-Mobile. What's interesting doesn't have with a verizon sim in the phone. Its a 5G SA issue that's causing it.

Yeah I would already have just unlocked my bootloader if oneplus would just send the token [emoji23]

Its just sad one gets a better call/text experience on a $100 phone than an $700 phone
[OnePlus 8 Guides, News, & Discussion] batchenv:
Device Certification status in Play app

Question for those who applied Global Conversion and update to A11 on TMO phone:

Does it pass Device certification in Play Store app (at the bottom of Settings menu showing 'Device is certified')? This I think allows Google Pay working without issues and install/streaming on some apps.

Thank you! I ask because on 6T TMO updates on Global worked fine at first but after A10 update it started showing 'Device is not certified' and required rooting.
[OnePlus 8 Guides, News, & Discussion] erik29gamer:
I have a T-Mobile 8 running the newest global ROM. Bootloader re-locked. Shows "Device is certified" for me!
[OnePlus 8 Guides, News, & Discussion] batchenv:
Thank you! I went ahead and converted using the guidance here to Global 10.5.12 and then A11 stable and bootloader relock without problems . Can confirm as well that it shows certified after conversion and working smoothly so far.
[OnePlus 8 Guides, News, & Discussion] sx10:
SA only works with the latest IN2017 update, which is 10.5.22. The modem from that firmware does not work on Global/A11.

If you want to keep 5G SA i'd suggest staying on the Tmobile firmware, just unlock and root it.
[OnePlus 8 Guides, News, & Discussion] hyelton:
I've had SA since the Aug update months ago. Which is when all the problems started
[OnePlus 8 Guides, News, & Discussion] mslezak:
What program did you use to see this? As mine connects to 5G SA I use Cell Mapper and LTE Discovery. On A11 Global.
[OnePlus 8 Guides, News, & Discussion] coolqf01:
<Delete>
[OnePlus 8 Guides, News, & Discussion] coolqf01:
How did you relock the bootloader?
[OnePlus 8 Guides, News, & Discussion] esjames:
I can say from my personal experience that the A11 modem does work, I just cant get it to roam onto the sprint bands B25/B26. If someone has figured this out please share :)
[OnePlus 8 Guides, News, & Discussion] deepeshm:
Does anyone know how to bypass the invalid IMEI error from T-Mobile? I am trying this on a Oneplus 8t.
[OnePlus 8 Guides, News, & Discussion] hyelton:
Is the phone network unlocked yet?
[OnePlus 8 Guides, News, & Discussion] erik29gamer:
Sorry for taking a while to get back. I stuck my T-Mobile SIM in the bottom side slot, SIM 2. It detects the SIM fine, but shows no service. So there is absolutely contacts for the 2nd slot.

[IMG="SIM2"]https://imgur.com/a/eJTYYTu[/IMG]

https://imgur.com/a/eJTYYTu
[OnePlus 8 Guides, News, & Discussion] mslezak:
I tried again with a live sim. The internet settings show the right carrier but I can't get a connection to the internet or make a phone call. Checked the APN. The slot is there but as far as I can tell, you can't use it. It says no active connection. So still, I say 1 SIM on a TMO phone.
[OnePlus 8 Guides, News, & Discussion] deepeshm:
It is network unlocked.
[OnePlus 8 Guides, News, & Discussion] xxBrun0xx:
Just wanted to chime in. I kept having " no sim detected" messages appear after converting my t-mobile OnePlus 8. I run a TMobile sim. Turns out the sim itself went bad. Replaced it with a new sim and have had zero network issues on A11 global modem since. Weird issue, but easy to fix.
[OnePlus 8 Guides, News, & Discussion] rzracer2:
I converted to Android 10 global then took the update to 11 and another update to 11.0.1.1. I went to boot into the latest TWRP image so I could backup boot to root it but always boots to Qualcomm crash dump screen. Tried older versions but the same outcome. Other then that, fingerprint and modem seems to be working fine with no extra work. Thanks