Chosen Solution
I have changed the boot mode to legacy and changed the order so it checks the usb first but it doesn’t work it says missing operating system
Hi @Mark Emmo, Check if the following options are enabled in BIOS or at least the first one BIOS > System Configuration > USB Configuration > Enable Boot Support : Enable or disable booting from USB mass storage devices such as external hard drive, optical drive, and USB drive. Enable External USB Port : Enable or disable booting from USB mass storage devices connected to external USB port.
Your BIOS may be different from my Dell, but this is how I have mine setup for USB boot after I reinstalled Windows 10. I would try setting the following on it, but I will also give you visual clues. I HAVE seen this BIOS on a 9th gen Inspiron desktop, so I’m thinking Dell may have changed things in recent years and switched over to one BIOS skin. USB Configuration: Enable Boot Support and External USB bootBoot sequence: Make sure UEFI is enabled and Windows Boot Manager is first. UEFI Hard Drive should be next. Once you make those changes, press F12 and select the USB flash drive. At this point, you should not have an issue but you may need to temporarily disable Secure Boot. I personally leave it off permanently, but it does have some security benefits for average users which justify re-enabling it. I sometimes run Linux on my systems, and few distros properly support it.
Windows 10 Home will not boot in Legacy Mode. In order for the computer to recognize the USB, you will have to change that setting back.
