Dear Prasit,
If you need to reset vivofit 3 to shipping mode, we now have a tool you can use.
Unzip the attached .zip file and you will find ANTCommander.exe.
Please follow the steps below:
1. Make sure device is switched to Pair.
2. Plug in ANT+ Stick on PC.
3. Open ANTCommander and press Connect.
4. Wait until progress completes.
And we are sorry to make confusion about the method to get monitor folder from vivofit3.
After confirmed with engineer, users cannot enter mass storage mode of this model.
We will keep improving the algorithm of Move IQ feature.
Thank you.
Sincerely,