Because W10 can have difficulty overwriting the Ubuntu drive format, you may have to do a "drive-wipe" of your hard drive before it will accept a new W10 install from USB or DVD. I recommend you use DBAN for this, and the free version from UBCD.com will do just fine. It's the same basic wipe used by DoD without all the advanced encryption. Make sure you check that if you have UEFI BIOS, that it is disabled AND also that if you have a legacy boot option in your BIOS and it's set to SECURE, you have to disable that as well in order to boot from a USB drive. You should also attempt to boot your W10 boot USB on a different working windows computer (can be Vista-W10) and check that it indeed comes up to the W10 install program. If it doesn't do this on a different computer, then either the W10 source ISO file you used was bad (did you download directly from the Microsoft website or 3rd party such as uTorrent?)? Or your USB drive is bad or wrongly formatted. Just remember that when testing your USB W10 drive on a 2nd computer, to exit out after the 1st install screen so you don't inadvertently overlay W10 on an older windows PC such as W7 or W8.
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