Sony Flashtool (also known as Sony Mobile Flasher) is a third-party desktop application developed by Androxyde. It allows users to flash stock firmware (.FTF files) onto Xperia smartphones and tablets. While Sony provides its own official Flash Tool , the community-developed Flashtool is widely used for its additional features like rooting and bootloader management. Flashtool - 4PDA

Newer versions (0.9.20+, 0.9.23+) introduced support for Xperia X and XZ series but also increased complexity, driver conflicts, and occasional bugs with older chipsets (Snapdragon S4, 800, 801). Version 0.9.18.6 is lean, predictable, and rarely crashes mid-flash.

: Removing carrier-specific software by flashing generic "unbranded" firmware. Downgrading

On Windows 10 or 11, you must disable Driver Signature Enforcement in the Advanced Startup settings to install Flashtool drivers.

: Place your downloaded firmware file into the C:/Flashtool/firmwares folder on your computer.

If the phone hangs, try flashing again without skipping the "Wipe" steps.