1. On phone, touch Settings > About Phone touch 7 times at MIUI version
2. Additional Settings > Developer options > USB Debugging enable
3. Connect phone and PC with USB cable
4. On your PC, right click and chose open command window here
5. Typing adb shell, enter
6. Typing adb su, enter
1. Download ADB and stock rom.zip at end thread.
2. Power off your phone
3. Boot into stock recovery (press volume up + power key)
4. Extract adb.zip, in adb folder, right click and chose open command window here
5. Typing adb sideload, then drag and drop rom file into CMD window, press Enter key and wating finish.