1. Unpack FlashTools, and Click on Flash_tool.exe
2. Select a the scatter.txt in folder qmobile ROM
3. Wait file to be added into Flash Tool
4. choose Option->USB Model,click USB Model
–> Choose Option->DA DownLoad All->Speed->High Speed, click High Speed
5 Turn off your phone, remove the battery.
6. “Press F9 (hit Download button)” OR ” if upgrade ROM firmware ->Upgrade “
7. and connect your phone into the computer via USB data cable.
8. The process will start and a red progress bar will appear after color purple, yellow.
9. And green circles display
10. Finish !
– You can now safely disconnect your phone and turn it on
Qmobile Qtab Q300 custom
4.4.2 jelly bean