This article provides the information on "Dell systems shipped with the Windows 10 to Windows 7 downgrade fail to boot to Dell Windows 10 media".
If your system shipped from Dell with the Windows 10 to Windows 7 downgrade option, it was configured with the Basic Input/Output System (BIOS) in the "Legacy Mode". The Legacy Mode allows for a non Unified Extensible Firmware Interface (UEFI) operating system installation.
When you attempt to boot to Dell Windows 10 recovery media on a system configured in the Legacy Mode, no Boot Device errors may be encountered.
There is no diagnostic failure of the system, no hardware failure detected.
This occurs because all Dell Windows 10 recovery media (Win10 recovery DVD [Clean install only from DVD] or WIN10 recovery USB key) require the system BIOS to be configured in the Unified Extensible Firmware Interface (UEFI) mode.
There will be no changes made to the Dell Windows 10 recovery media because, as by Microsoft design, Windows 10 is intended to be used in the UEFI mode configuration.
If your system was shipped with Windows 7 installed and the BIOS configured to the Legacy mode, you should back up your data then the re-image the system with Dell Windows 10 recovery media with the BIOS configured in the UEFI mode. All applications and software will also need to be reinstalled because when the BIOS is switched from Legacy mode to UEFI mode it will render the existing Windows 7 installation unreadable.
The steps to change from Legacy to UEFI boot configuration
For information on obtaining recovery media for your Dell computer, refer to the Dell Media Backup page.
Article ID: SLN300634
Last Date Modified: 02/26/2018 10:09 AM
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