Booting using ISO file

[Philip54]

You are correct. I am at an impasse. Thanks for stepping in to help.

However the issue is not whether to boot up from a USB memory stick or a DVD. I have not quite got to that point. As Hibb1 suggested in another post of this thread, when restarting the PC, with the bootable USB memory stick installed, I am supposed to keep tapping ESC or F9 until a menu with various options (including how to boot), is displayed on the screen. For reasons unknown to me, that does not happen on my PC and a black screen with nothing to choose from is displayed all the time.

Any help from you and/or others will be appreciated.

[Philip54]

The computer model is HP Pavilion Elite HPE-150t.  The product number is BN474AV-ABA

[Prométhée]

We can try in different ways ..
You can sometimes have the menu actually once you press the start button.
And immediately tap the escape key then f9 in order to go to the menu

Access the BIOS Setup utility using a series of key presses during the boot process.

1. Turn off the computer and wait five seconds.
2. Turn on the computer, and then immediately press the Esc key repeatedly until the Startup Menu opens.

But we can directly start the bios menu, by tapping the f10 key several times and modify the boot options

To open the BIOS Setup utility, turn on the computer and immediately press the F10 key repeatedly, about once every second, until the BIOS setup utility screen opens.

Choose menu screens by pressing the left or right arrow keys. Use the up or down arrow keys to move up or down through the list of items on a menu screen. Press the Enter key to select an item. For certain items, pressing the Enter key opens a submenu. After you have selected a menu item, use the arrow keys to modify the settings. Press the Esc key to exit from a submenu. Help is shown on the right side of the screen.

https://support.hp.com/us-en/product/hp-pavilion-elite-hpe-100-desktop-pc-series/4079700/document/c0...

I therefore advise to try to directly check the bios options available with the USB key!

[Philip54]

Thanks for your help.  I was able to boot from the USB that I had prepared with Rufus, but I got the following error message:

Quote    This drive can only boot in UEFI mode.  It cannot boot in BIOS/Legacy mode   Unquote

I tried to prepare another image file on my USB memory stick using Rufus, but I had no success.

Could you or others recommend an alternative software to Rufus to prepare an image file on my USB memory stick that can boot in BIOS/Legacy mode?  I don't mind paying a small licensing fee, if this alternative software is not available for free.

I don't know how to the get the computer to boot in UEFI mode.

Thanks