Guide up stockrom 

1. Open the folder SP_Flash_Tool_v3.xxxx

2. run Flash_tool.exe

3. Choose Scatter-loading

4. Select the path to the folder that contains software> image folder> select file MT6577_Android_scatter_emmc.txt> Open

5.select download

6. Turn off => remove the battery => attached cables => insert the battery => computer will require software drivers for dt => double click on the icon to install drivers

Choose Skip optaining driver software from Windows Update

Select Yes

Click on the icon ransom My Computer> Manage

Select Devive Manager

Click on Disturbed device must atone> Update driver software

Choose Browse my computer for driver software

Select Browse> leading to the folder containing the USB driver VCOM Driver> select the folder that corresponds to the version you use Win

Select Next

Select Install driver software anyway
Wait for the machine installed drivers

7.Cho until finished loading FlashTool . done