My Venue 8 Pro was working perfectly under 8.1, but after the update to Win 10 the tablet will boot up, let me log on with my PIN, then goes to the desktop and just continuously will flash between a blank desktop, the apps and the desktop picture. I can not access anything at all.  I have been sent a cable and USB drive to use to reset my system to 8.1, but.... none of the instructions I am receiving from the people I've worked with will get the tablet to boot from the USB. (I have been using the Dell facebook page and working with the people who answer the FB messenger... )  In any case....  I want my tablet to work... at this point, I don't care if it's Win 8.1 or 10.  If anyone can give me direction on how to get the tablet to actually boot from the USB or any other information on how to proceed.