Unable to boot from Kyhi's boot USB

Some time ago I created a number of bootable USB drives for diagnostic, recovery, etc. purposes. These include Kyhi, Hiren, Macrium.

Wanted to run Memtest86+ so tried to boot from Kyhi, nothing, the USB drive just sat there with the LED gently pulsing away for 10 minutes until I gave up. Tried Hiren, worked immediately.

Thought perhaps the Kyhi had got corrupted so recreated it. Still no joy.

Reformatted the USB drive and recreated. Still no joy.

Got a brand new USB stick and tried with that. Still no joy.

I created the drive with Rufus 3.1 and am wondering if I have the options wrong.

I took the defaults. These were:
use an ISO image: winpese-x64-14393_17.01.16.iso
Partition scheme: GPT - the alternative was MBR
Target system: UEFI (non CSM) - no alternative listed
File system: FAT32
Cluster size: 8192 bytes

Is there any way of determining whether these are correct, such as looking at, say, the Hiren's drive and seeing how that is set up?

I wonder whether I should have used MBR. I notice if I select MBR the Target system changes to BIOS (or UEFI-CSM)

Thoughts would be appreciated.

See these links:

Boot from USB Drive on Windows 10 PC

If you have fast boot or ultra fast boot enabled in your UEFI firmware settings, then you will need to temporarily disable fast boot or ultra fast boot to be able to boot from a USB.
How to Enable Fast Boot or Ultra Fast Boot in UEFI Firmware Settings for Windows: Enable or Disable Fast Boot in UEFI Firmware Settings for Windows

Thanks for that swift reply, some food for thought.

Though as the Hiren and Macrium USB drives boot OK, and as far as I can recall were created at the same time, it seems odd that Khyi USB drive fails to boot.

Code:

diskpart
list disk
select disk # <- replace # with the disk number of the usb flash drive
clean <- this will erase the flash drive
create part pri
format fs=fat32 quick
active
assign
exit
exit

Thanks. Did that. The "active" command failed

The selected disc is not a fixed MBR disk.
The ACTIVE command can only be used on fixed MBR disks

If the flash drive is MBR with a FAT32 partition marked as active it will be universally bootable in legacy BIOS, UEFI and UEFI in CSM modes.

Unless it was recently changed Rufus does not have the FAT32 option, just NTFS.

Thanks to you both.

I followed Megahertz instructions and, apart from having to change the default program for .iso as I wasn't offered Mount in the context menu, it all worked.

Double checked, Rufus 3.1 which I downloaded in July 2018 offers both FAT32 & NTFS, with FAT32 as the default.

I'll mark this as solved.

Thank you both. As someone put it to me recently "every day is a school day", learning something new.

Nice.
You're welcome.
So the operating system is working well and the boot rescue is to create the tool in case it's needed in the future?

I'm comfortable tat the OS seems to be running sweetly - at the moment... though I may have a hardware problem mentioned in another thread

I prefer to be prepared - just in case!