1. Preparation, need 1 tool: Microsoft Windows Mobile Device Center 6.1-for Windows Vista, can download http://www.microsoft.com/downloads/zh-cn/details.aspx from Microsoft website? Familyid = 4f68eb56-7825-43b2-ac89-2030ed98ed95
2. Prepare the DFT Rom, which can be downloaded from the http://115.com/file/e6rr2unq.
3. Install Windows Mobile Device Center 6.1 in Windows 7 and decompress the 7720 ROM of DFT.
4. Close your phone, press and hold the volume key down, press and hold the power key again, and then press the three-color mode to connect to your computer with a USB cable:
After the driver is installed on the computer, serial is changed to USB.
Run romupdateutility.exe on the 5th node.
Tick, next
Click Update
Press next to start flashing
After you press next, the scroll bar will appear. Wait a few minutes and the progress bar will reach 100%.