1. Step 1.Install the upgrade tool first in your copmputer.

2. Step2: Press”Start”-”Programs” and you will find “Mobile Production Tool Pack” and then “Mobile Production Download Tool(ASS)”

3. Step 3: User choose “Engineer” Station choose “RE-DL” Password input “mst789”

4. Step 4: 1.Press “USB Configuration” 2.Press Start config and then connect the phone and you computer with download cabel (No need battery) 3.After the tool showed the ID numbers, press”Config over” and remove the download cabel.

5. Step 5: 1.Press below part to choose the DZ file.

6. Step 6: After choose the DZ file, tool will show as below.

7. Step 7: Press “status” connect your computer and phone again, upgrade will proceed Automatically(Also without battery).

8. During upgrade

9. Upgrade finished! After upgrade the SW, pls restore factory setting for the phone Password “1122”