External boot device (CD/DVD, HDD) not displayed in boot menu

[admin]

When you want to boot from an external boot device, e.g. an external CD/DVD reader or HDD, it might be possible that the device doesn't appear in the boot menu. (to call the boot menu, tap <F7> while booting your mini-PC).

I wanted to boot an original Windows DVD on an old external DVD writer and couldn't find my writer on the list.
There's a solution however. You need to change some settings in the UEFI environment.

Original Boot Menu.png (233.65 KiB) Viewed 1040 times

Select <Enter Setup> in the boot menu or reboot your
mini-pc and tap the <Delete> button to enter UEFI.
Click on the <Advanced> tab and select <CSM Configuration>.

CSM Configuration.png (111.53 KiB) Viewed 1040 times

In the "Compatibility Support Module Configuration" menu:
Set "CSM Support" to [Enabled] to reveal the extra settings.
Set the "Boot option filter" to [UEFI and Legacy].

Compatibility Support Module Configuration.png (119.9 KiB) Viewed 1040 times

Save the new settings and reboot your mini-PC.
There will be one or more new devices in the boot menu!

CD DVD Boot Device in Boot Menu.jpg (123.33 KiB) Viewed 1040 times