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I'm trying to create a bootable windows 7 installation USB drive through Ubuntu. I was recommended to use PowerISO to do this, however the software isn't recognizing any of my USB flashdrives. I've tried using Unetbootin, WinUSB, Startup disk creator, and Universal USB Installer, but have had several problems with those too. I don't have a disk drive or another computer with windows otherwise I wouldn't have this problem in the first place. Thanks in advance.