opoo f7 demo file not flash

Unstable comport
Definition Applied
1. Power Off Phone , Remove Battery, Insert Battery Back
2. Insert USB cable. In some cases Required Hold BootKey
3. Use Miracle Boot Key In cases Boot key not Find
4. Battery Should be Charged more then 50%
Waiting for USB Port...
Set MediaTek USB Port (COM170)
Connecting to Phone,Wait..
Connected to Phone.
CPU: MT6771 SW:0000 Ver: CA00
>>Downloading Boot8 ...