How to install official firmware on tablet ViewSonic ViewPad 10s

This method can be applied to any firmware when flashing, using NvFlash mode (some require full wipe).
Step by step guide on how to update the device ViewSonic ViewPad 10s to the latest official firmware with the help of Windows PC.
You'll need:
- the device;
- power adapter;
- male-to-male USB cable;
- working computer with Internet connection.
Getting ready
1. Make a backup of the personal data and settings to the SD card using built-in program (search in settings) or third-party software (such as Titanium Backup Pro).
2. Make sure the battery is fully charged and the power adapter is plugged in.
3. Download and extract firmware update and USB drivers into a folder on your computer. Make sure that all the ZIP files are unzipped.
4. Turn off the device. Make sure it is not in a sleep mode, but actually turned off.
Full wipe - complete deletion of the entire system, necessary for stable operation before another firmware is installed.
5. Connect the device to PC using USB cable.
6. Boot into recovery mode.
- Hold the down "Buton1" (back) for 1 second.
- While holding "Button1" press "Button2" (power) and also hold it for 1 second.
- Release "Button2".
- After a second release "Button1".
- If you did everything correctly, Windows will see the device and alert with a beep on connecting.
7. On your PC, go to "Device Manager".
8. Right-click the "APX" device without a driver and select "Update Device Software".
9. In the popped up list click "Browse my computer for driver software" and specify the path to the unzipped folder that contains the drivers.
10. Ignore any security warnings that advice you to check the drivers.
11. Click the "Close" button to complete the update.
12. In the "Device Manager" there'll be new driver.
13. All done, drives installed.
14. Run the downloaded exe file which contains the firmware.
The device will display the same message as in the photo below.
15. Wait until a message about the successful completion of the firmware appears.
After completion, the device will automatically turn off.
16. You can check the updates results by following this path: Menu → Settings → About Device. For example "2.6.32.9_P10_V1.09_20110210_VIE" firmware version 1.09.
17. After the flash, commence the screen calibration. Menu → TP Utility → Recalibration. Disconnect power adapter, then click "OK". Do not touch the screen until the process of calibration is completed.
If you want to stop the process of upgrading and go before step 10, hold down the power button for 6 seconds. The device will exit the upgrade mode.
Conclusion
Important notice: do not repair or modify this device if it's still under warranty.