How to update or install the ROM on Galaxy S21 + with a newer version of Android using the Odin3 application or restore to an earlier version known as «downgrade».
With this process, we will not lose any of our data, applications or files saved on our mobile device, but, optionally, we can also format it to apply a clean installation of the system.
In general, it is ideal to create a full backup of the contents of your mobile device, for this purpose it is best to use the free and official Samsung Smart Switch software.
Updating a Galaxy S21 + terminal is a very easy process and will leave our mobile device with the completely original Android firmware, managing to solve all the problems related to the software that may appear on the Smartphone.
In the following lines we leave you everything you need to update the Samsung Galaxy S21 + firmware.
How to update Samsung Galaxy S21 + using Odin3 application
In the Galaxy S21 + configuration we have to go to the settings to activate USB debugging from development options.
If we don’t have these options enabled for developers, we need to enable them from About the device, Software information by pressing seven times per section construction number.
First we download the necessary files to our computer.
- I downloaded the latest version of Odin 3 for Windows.
- I downloaded the USB drivers for Samsung Galaxy S21 + phones for Windows.
- And finally, we download the updated rom for Samsung Galaxy S21 + and extract it from our computer.
Then, we install the USB drivers from our phone to the computer and start the Odin application.
We turn off Galaxy S21 + and start it in download mode, for this we hold down the buttons together smaller volume + start + power to release even when the download mode entry appears.
Then, after releasing all the buttons, press the volume up button to accept.
In the download mode we start the Odin3 software and connect Galaxy S21 + to the computer via the USB data cable, then we can see the text added in the Odin 3 window.
This means that for the moment everything is going well and the communication between our terminal and the software is correct, otherwise we should check the USB connections, the cable and, if convenient, reinstall the drivers as well.
Now all you have to do is load all the rom components in the Odin 3 application using the corresponding buttons.
To do this, we will first click on the BL button, we will go to the folder where we extracted the rom and we will load the file that starts with BL_, then we will click on the open button.
We repeat the same for the AP_ and CP_ files.
Then, before pressing the CSC button and preparing to open the corresponding file, we need to think about the deadline79. we want to apply on the Samsung Galaxy S21 + device.
- Update / reinstall the ROM without deleting the current data or applications.
- Or clean everything and lock the clean firmware, with which all the contents of the internal memory, as well as the settings and accounts will be permanently deleted.
- To update the Galaxy S21 + ROM by installing the system without losing the contents, we need to load HOME_CSC_.
- To update the Galaxy S21 + ROM at the same time we format the mobile phone to get a clean system, we will open CSC_ instead.
Note: It is recommended that you always use HOME_CSC_ unless the system is severely damaged.
After uploading the files we analyzed in the previous step, we click the Start button and the update process will begin.
And, to finish, we wait a few minutes until the progress bar is completed and Samsung Galaxy S21 + restarts, just then we will have to remove the USB cable, close the Odin utility and wait a few seconds while our mobile phone restarts .