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Irwin W.Flag for Canada

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EFI USB Boot issues

I have a new swanky Lenovo Yoga S260 laptop.

I am attempting to downgrade it to Windows 7 but having some issues.

I have created a bootable USB thumb drive and verified it works but just not with this Yoga laptop.

One other thing to note is that secure boot is disabled so that USB booting is permitted.

Here is a screenshot of the error I receive.

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Avatar of Pawan Kumar
Pawan Kumar
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Try to reboot in DOS mode or Safe Mode.

Also check whether the BIOS detects the motherboard.
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This is a Windows installer USB thumb drive . There is no booting into. DOS.

This computer is a uefi only bios.

As mentioned this bootable thumb drive works on other computers.
You have to select which boot from USB, MBR or UEFI.  With my Bios I use the F8 key on boot and I will see various options i.e.
Hard Disk 1
Hard Disk 2
Hard Disk 8

If I have both a dual boot DVD and USB drive connected
if you point it to the correct boot device - it should be able to boot
you can also test the usb device on other usb ports - usb 2 or 3
Make sure the USB stick is formatted to FAT32. If it uses NTFS you can't boot it in EFI mode.
Ditto rindi. Is it FAT formatted?
As mentioned in my original post; "I have created a bootable USB thumb drive and verified it works but just not with this Yoga laptop."

Also, this flash drive is selected from a boot menu using the F12 key. F8 is not an option on the Lenovo BIOS.

The drive is properly formatted using these commands:
-list disk
-select disk 1
-create partition primary
-select partition 1
-format fs=fat32 quick
-copied ISO files to flash drive
-made efi\boot dir
-copied \windows\boot\efi\

Any other suggestions?
Use the tool "WinSetupFromUSB" to create the boot stick. It is easy to use and works well:
Same issue with this tool.
If your PC has USB 2 ports, try booting from those. If not, check the BIOS settings, you might be able to change how the USB ports work.
All ports causing the same issue.
Did you check the BIOS whether there is something you can tweak for the USB ports?
test the stick on another system - it can be bad,
or there is something wrong on this system - are you on the latest bios update?
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Irwin W.
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Self resolved.