Use the process below to boot your Douro's tablet to a reimaging USB drive.
Entering the BIOS
Power off the Douro with a single press and release of the power button at the top of the tablet.
Insert the flashed USB drive into the blue USB 3.0 port on the top of the Douro's tablet. (Some models may not have a 3.0 port, in which case use any available one.)
Connect a USB keyboard to one of the tablet's other ports.
Press the tablet's power button, then repeatedly hit the DEL key on the keyboard until the tablet boots into the BIOS settings screen.
Selecting the Boot Drive
Use the arrow keys and Enter to select the following screens and options.
1. Select the Boot screen > Hard Drive BBS Priorities
2. Select Boot Option #1 (mSATA mini 3ME3...)
3. Set Boot Option #1 to Disabled.
4. The USB flash drive should remain as the only option. Hit the ESC key.
5. Under 'Boot Option Priorites', disable Boot Option #2.
6. Now only the USB flash drive will be the only boot option.
7. Navigate to the Save & Exit panel, then 'Save Changes and Reset'.
The machine should now boot from the drive. Continue with the steps found in 'Reimaging the Douro's drive'.