Comment 5 for bug 1775712

1) perhaps try running the windows version of unetbootin? sometimes there's trouble writing to mbr on linux systems. 2) if that one still doesn't work, try reformatting your USB drive as fat32 from windows? the fact that there's some phantom grub install on the usb drive seems troubling and suggests the formatting tool didn't actually format the MBR. the bootloader installed to the MBR has always been syslinux, grub is only used on EFI systems, and I'm assuming by netbook you mean a pre-EFI system 3) you could try an older version of unetbootin from https://github.com/unetbootin/unetbootin/releases say 638 if it is indeed a regression, I wouldn't expect so because I don't believe I've modified anything relating to bootloader installation but you could try