I have used rufus-4.9.exe and created a boot USB however when I attempt to boot from the USB I get a “Load Failure: [26] Security Violation”. the system does see the USB drive and the NTFS partition on it. Right before the load failure I get a "Launching ‘EFI\BOOT\BOOTX64.EFI’…
I am new to this and thought i was doing well 
if anyone can help I would apricate it.
thank you in advance
Check your BIOS. Is Secure Boot on? Try turning it off.
thank you for the reply
I get a message “unknown file system” and a prompt for “Grub Recovery”
Should I formatting the USB as DD or ISO? or FAT vs NTFS
This is what I get when looking at Rufus. Are you trying a different program to create the USB?
If you have to wipe the USB first, choose ‘Non Bootable’ from the Boot selection drop down. Let it wipe the USB and then choose like I have to create TrueNAS USB.
If you are having trouble at a different stage, let me know. Not sure if you got it installed on Optiplex nor what your hardware is.
I have rufus installed on a secondary machine that i am using to format the USB drive. There is a new 512gb M.2 installed in the Optiplex that I want to use as the primary drive for TrueNas
I looked in the BIOS and did not find a “windows/other” setting for the OS
I did try using FAT32, and that just gave me a message unrecognized file system
I cannot upload a screen shot, however what i have matches yours
thanks
The USB, once Rufus formats and loads the image on it, won’t be readable by Windows. You should be able to use it to boot a computer from the USB.
The USB, once booted and you choose to install on the 512GB M.2, will format and overwrite whatever filesystem is there.
I got it to work, thank you 
The thing i was missing was I needed to format the USB drive in DD not ISO mode. Once it did that it booted right into the installer.
when you said “your computer will not be able to read the USB stick” i remembered reading that somewhere. DD format warns about that exact thing.
