How To Install Stock Firmware On Sony Xperia using Xperifirm And Flashtool

This guide shows how to install the official stock firmware on a Sony Xperia using XperiFirm and Flashtool. There are a few reasons you might want to flash it manually: your region is slow to get an OTA update and you would rather not wait, a new update turned out buggy and you want to roll back to a stable build, or a custom ROM or root attempt left the phone soft-bricked or stuck in a bootloop. In each case, flashing the stock firmware puts the phone back on official software.

How the process works

Flashing an Xperia is a little different from other phones, and it uses two tools. XperiFirm downloads the official firmware for your exact model. Flashtool then turns that firmware into an FTF file, which is the format you can flash, and writes it to the phone in Flashmode. So the order is: download with XperiFirm, build the FTF in Flashtool, then flash it. One useful point: this method works on a locked bootloader, since you are flashing Sony’s own signed firmware.

Prerequisites

• Take a complete backup of your Xperia, since flashing can wipe it.
• Install the Sony USB drivers on your PC.
• Enable USB debugging: go to Settings > About phone, tap Build number seven times, then turn on USB debugging under Developer options.
• Download XperiFirm (it also comes bundled with Flashtool).
• Download and install Flashtool on your PC.
• Charge the phone to at least 60%.

How to install the stock firmware on a Sony Xperia

The process has three parts: download the firmware with XperiFirm, create an FTF file with Flashtool, then flash that FTF.

Step 1: Download the stock firmware

1. Open XperiFirm on your PC.
2. Select your device from the list on the left, then pick the firmware (and regional variant) on the right.
3. Check the firmware details, then click Download.
4. When it finishes, you will see an “Unpacked Successfully” message. Note the folder where the firmware was saved.

Step 2: Create the FTF file

1. Open Flashtool, then click Tools in the top menu.
2. Choose Bundles, then Create.
3. Under Select Source Folder, browse to the folder where XperiFirm saved the downloaded firmware in Step 1.
4. In the Device field, select your Xperia model.
5. Give the firmware a name under Branding, and a version number if you like (optional).
6. Move all the files from the Firmware Content list on the right to the Folder list on the left (use the arrow buttons), then click Create.
7. Wait for it to finish. You now have an FTF file ready to flash.

Step 3: Flash the FTF file

1. In Flashtool, click the Flash (lightning) icon at the top left.
2. In the Boot mode chooser, select Flashmode and click OK.
3. Under Firmware, select the FTF file you just created.
4. Under Wipe, tick DATA, CACHE, and APPSLOG (leaving DATA unticked keeps your data, but a clean flash is more reliable).
5. Click Flash. Flashtool will ask you to put the phone into Flashmode.
6. Power off the phone and unplug it. Hold the Volume Down button and, while holding it, connect the phone to the PC with a USB cable. The notification LED should turn green.
7. Flashing begins and takes a few minutes. When you see the “Flashing finished” message, unplug the phone and boot it. The first boot can take a while.

FAQ

Do I need to unlock the bootloader to flash stock firmware?

No. Flashtool flashes Sony’s official signed firmware, so it works on a locked bootloader. Unlocking is only needed for custom ROMs, recoveries, or rooting.

Will flashing erase my data?

It depends on the Wipe options. Ticking DATA wipes the phone; leaving it unticked can keep your data, but back up first either way.

Can I downgrade to an older firmware?

Usually yes with Flashtool, which is one of its main uses. Note that some Xperia models block downgrading certain partitions, so a downgrade can occasionally fail.

Flashtool does not support my newer Xperia. What do I do?

Flashtool covers most older and mid-range Xperia models. For some of the newest devices you may need Sony’s Newflasher tool instead, using the firmware downloaded by XperiFirm.

The PC does not detect my phone in Flashmode.

Install the Sony USB (Flashmode) drivers, use a rear USB port, and make sure you hold Volume Down before connecting the cable so the LED turns green.

That covers installing the stock firmware on a Sony Xperia with XperiFirm and Flashtool. If you run into any trouble, leave a comment below.