COM3 Port is busy – Error while flashing TWRP

Frederick Jerome — Fri, 10 Mar 2017 16:40:24 +0000

In case of COM3 Port is busy error while flashing TWRP on locked bootloader device. Here’s a solution that might work for you.

Solution for “0х800700aa: open serial port COM3” – Flash TWRP on Xiaomi Redmi 3

Run MiFlashClean.cmd (should be in folder with MiFlash.exe)
If you can’t find MiFlashClean.cmd, then here’s the code inside of this file:
```
del /q MiFlash-*.log
rundll32 qcCoInstaller.dll,qcInitializeSetting
```
Right click on MiFlashClean.cmd and select “Run as administrator”.
Try to flash TWRP again, error should be fixed.