This tutorial works for both flashing Microsoft Lumia Devices and Downgrading to windows 8.1 from 10 Mobile For flashing lumia devices you need: ● A compatible USB cable to connect the Microsoft Lumia device to the computer. ● A computer with Windows 7,8,8.1 or 10 operating system. ● A Microsoft Lumia device with Windows Phone 8,8.1 or 10 Mobile operating system. ● Backup the user content of the Microsoft Lumia device (optional). ● Minimum 4 GB free storage space from the computer. Downloads: You must need these things to downgrade/flash your device. Download it from below: Windows Device Recovery Tool: Official Installer Link: Direct Link: Windows Device Recovery Tool Download Page: Windows Device Recovery Tool Firmware: lumiafirmware.com Installation/flashing Process: ● Create a new folder on desktop and rename it to " Package ". ● Move the *.ffu file to this folder and rename it to " FullFlashUpdate.ffu ".