The OS does not match the system requirements of the smartphone.
Where can I find the firmware?
On the official Internet resource of the phone manufacturer.
On specialized services where users post custom or official OS.
What should be done before installing the firmware?
Create a backup copy of user data, contacts and photos and transfer it to your computer.
Insert an SD card into your phone to write the firmware to it.
Find information about your smartphone model.
Fully charge your phone battery.
Find and download the archive with Firmware.
Installing TWRP Recovery
Download and install the Official TWRP App from the Play Market.
When you start the application for the first time, you need to give consent to future manipulations, as well as to give consent to granting the application Superuser rights and click the 'OK' button.
After moving to the next screen, select the 'TWRP FLASH' item and provide the application with root rights.
On the main screen of the application, select 'Select Device', and find your phone model.
After selecting a device, the application will direct the user to a web page to download the appropriate modified recovery environment image file. Download the suggested *.img file.
When the file is loaded, you need to return to the main screen of the Official TWRP App and press the 'Select a file to flash' button. Select the file downloaded in the previous step.
Press the 'FLASH TO RECOVERY' button and confirm your choice, press 'OK'.
When the message 'Flash Completed Succsessfuly!' appears. Click 'OK'. The TWRP installation procedure can be considered complete.
Copy the required files to the memory card. Using a PC or laptop card reader.
Insert a memory card into your phone.
To reboot into recovery, you need to use a special item in the Official TWRP App menu, accessible by pressing the button with three stripes in the upper left corner of the main screen of the application. We open the menu, select the 'Reboot' item, and then click on the 'REBOOT RECOVERY' button. The phone will reboot into the recovery environment automatically.
Firmware via TWRP
Before flashing, you need to clear the 'Cache' and 'Data' sections, press 'WIPE' on the main screen. You will delete all user data from the phone, this will avoid software errors and other problems.
Now you can start flashing. Click the 'Install' button.
The file selection screen appears. At the very top there is a 'Storage' button for selecting an SD card.
Select the storage to which the files were copied.
Find the file we need and click on it. A screen opens with a warning about possible negative consequences, you need to check the item 'Zip signature verification', which will avoid using corrupted files when writing to the phone's memory sections.
The procedure for writing files to the phone's memory will begin, this is accompanied by the appearance of inscriptions in the log field and the movement of the progress bar.
The completion of the firmware installation procedure is indicated by the inscription 'Successful'.
Summary: Aliases: Sony Xperia U, SonyEricsson Kumquat; Type: Mobile; Battery: Li-Ion 1320 mAh; CPU: NovaThor U8500, Dual Core 1GHz, ARM Cortex A9, ARM Mali-400; Eusar: 1.62 Head; Smart Phone OS: Android 2.3; Dimensions: 112 x 54 x 12 mm; Formfactor: Bar; Keyboard: Screen; Sidekeys: Volume, Camera, Lock; Softkeys: 3; Weight: 110 g; Color: Yes; Colors: 16M; Other: Capacitive Touchscreen, Multitouch, Touch Buttons, Scratch-Resistant Glass; Pixel aspect ratio: 1.50; Resolution: 480x854; Display PPI: 280; Screen Size: 3.5; Type: TFT; Audio: MP3, eAAC+, WMA, WAV; Camera: 5MP, 2592x1944; Other: Autofocus, Face Detection, Digital Zoom, Geo-Tagging, Panorama, Video Light, Video Calli ...
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