Here are the specs for your HP Pavilion 20-b010 All-in-One Desktop Computer. According to the specs, this model shipped with Windows 8 installed and therefore has a BIOS setting called "Secure Boot" that is enabled by default. The "Secure Boot" and/or the "Legacy Support" settings may need to be changed to allow you to successfully boot from and/or install many older or non-compatible operating systems. Changing "Secure Boot to DISABLED and "Legacy Support" to ENABLED my solve your issue. Please see "BIOS Settings for the Azara and Azara2 Motherboards" for more information about the BIOS settings for your computer, including Secure Boot and Legacy Support.
Secure Boot Configuration is a new feature in BIOS 8 that allows your computer to validate the authenticity of components like firmware. When your computer was manufactured, UEFI created a list of keys that identify trusted firmware and OS loader code. It also created a list of keys to identify known malware. When Secure Boot is enabled, the computer checks that everything being loaded and used even before Windows opens is safe and recognized. Any malware or other firmware code that is not recognized is blocked. For example, Secure Boot can prevent your computer from starting from illegally copied CDs or DVDs that could harm the computer. Secure Boot does not lock out valid recovery discs or Windows discs.
NOTE:This option is available only with BIOS 8 and on computers with Windows 8 installed.
CAUTION:Changing the Secure Boot options can cause problems with your computer. Your computer might be more susceptible to viruses or malware, or it might not start correctly. Make only the changes necessary to secure your computer.
Before you can use this menu, a warning appears. If you have Windows 8 installed on your computer, press F10 to continue to the Secure Boot Configuration menu. If you do not have Windows 8 installed, press Esc to cancel.
Figure 24: Secure boot warning
Figure 25: Secure Boot Configuration Menu
The Secure Boot Configuration menu contains the following items:
Legacy Support - Select this option to boot up normally, without Secure Boot. Enabling Legacy Support automatically disables Secure Boot. Legacy Support allows any firmware or OS loader code to run.
Secure Boot - Select this option to enable Secure Boot. Enabling Secure Boot automatically disables Legacy Support.
Clear Secure Boot Keys - Select Clear to remove the list of recognized firmware, OS loader, and known malware keys. Select Don't clear to keep the keys created when the computer was manufactured.
Key Ownership - Select Custom keys to specify recognized firmware or OS loader keys. Select HP keys to use the keys created when the computer was manufactured.
Fast Boot - Enabling Fast Boot reduces the time it takes for your computer to boot up. During Fast Boot, USB devices are not available until the OS boots up completely.
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