[Samsung Galaxy S20 FE Guides, News, & Discussion] CSxKING_:
Hi there,

I normally don't make threads, post comments, etc. I've been into modding devices and changing things for some time now, however. I was annoyed that AT&T decided that they're either not going to release Android 12 or they're being slow and lazy, so I did what I used to do and manually updated. Here's how I did it. Sorry in advance if this is poorly formatted.

This guide is aimed towards people who are new in this field and/or just want to update already. Tested on AT&T variant of the S20 FE.

Note: I only have a Windows machine. This guide REQUIRES the use of a computer at the least, and this is written from the perspective of Windows users. I cannot help you if you are on MacOS or Linux.

1. Prep work

Download Frija 1.4.4. In the model text field, enter SM-G781U. In the CSC field, enter a carrier code which supports your carriers network. For example, AT&T uses GSM, so does T-Mobile. AT&T hasn't released Android 12 yet but T-Mobile has, so I used T-Mobile. Here's a few major carrier CSC codes.

VZW - Verizon Wireless

ATT - AT&T

TMB - T-Mobile

Once you've done the above, leave the "Auto" setting ticked and click on "Check Update". Frija should auto-fill ther Version, Size, OS, and Filename fields when it sees the update from the other carrier. Click Download.

Frija is now downloading Android 12 via the other carrier. This will take some time to complete.

While Frija downloads Android 12, head over to this thread and download Odin V3.14.1.zip. I wouldn't recommend the patched version, just use the normal one. Unzip this to somewhere you'll remember and in its own folder for organization purposes. You'll need it later.

Next, unlock your phone, remove your Pin, Fingerprints, Google account(s), and Samsung account, as they could hinder your ability to unlock your phone until the process is complete later on, as I learned.

If you have the Secure Folder enabled and use it, back up all data in it now. Do the same for anything you care about on internal storage. It will likely be lost otherwise.

2. Installation

I will reiterate once more, back up any data on Internal Storage and Secure Folder that you care about or it may be lost. I am not responsible for lost data. I will not help you if you didn't read and lost your data.

With that in mind, we'll begin with the installation process of Android 12. We'll do this as simply as I know how, and how I've done installs like this for years. You'll need a USB-C cable that's capable of Data transport. The one that came in the box should work fine, but so should most other cables. Basically, if your computer can see your phone, you're good.

Unlock your device, head down to About Phone -> Software Information and tap the build number until Developer Mode is enabled. It may ask for your pin/passcode/pattern if you haven't removed those yet.

If you don't know how to use ADB, you can enter Download mode via hardware keys. Please Google this.

Go back to the main settings screen, scroll down past what you thought was the end, and tap Developer Options. Enable USB Debugging and close settings. Connect your device to your computer, and allow the USB Debugging prompt making sure to tick Always Allow. Open a Command Prompt with ADB access and type "adb reboot download". This will immediately reboot your device to Odin Download Mode.

From here, open Odin, which you downloaded above. Unzip the file Frija downloaded to the same folder as Odin for organization. You'll end up with 6 files, each beginning with an abbreviation. You will only need 4 of these, they are as follows:

AP_

BL_

CP_

CSC_OYN_

You will not need the files beginning with HOME or USERDATA.

Within Odin, click the BL button. Select the file beginning with BL_. Then click the AP button, and select the file beginning with AP_, and so on. Odin will "verify" these files as you select them, and may appear unresponsive for some, in particular the AP_ file may take some time to verify. If you receive a not responding prompt from Windows, click wait.

Once all 4 files are selected, your phone is in Download mode, and Odin sees your phone (shown in the ID:COM field), press Start. This will now flash Android 12 to your device. This will take some time. Do not unplug your device until this process is complete! Doing so could result in a soft (or possibly hard) brick! When Odin completes the flash, you'll first see it say "RESET" then "PASS!". At the end, Odin should look something like this: View attachment 5511035

At this point, your device will now reboot. It should reboot straight into recovery, where it is now advised to Wipe Cache Partition, then Wipe Data/Factory Reset. You can use the volume keys to navigate the menu, and the power button to select. If you haven't backed up your data yet, this will be your last chance to do so, and you can reboot to Android by selecting the Reboot option at the top.

Failing to Wipe Cache and Factory Reset will most likely result in broken features, including but not limited to the ability to recieve Calls, Texts, use Mobile Data, or change your passcode/fingerprints.

Once you've finished Wiping Cache and Factory Resetting, you can reboot your device. Android will take some time to boot, and when it does you'll be prompted with your carriers boot screen, followed by the initial setup wizard for Android 12.

At this time, you've completed the process. Android 12 is installed and all functionality should be there. You can now restore your data from the backups you made and continue about your day with Android 12.

Hope this helped.