PE Boot disk

Hello,

I am currently evaluating various options for disk backup/cloning.  I have read a lot of nice things about AOMEI so I downloaded it, installed it, and was very pleased by the ease of use to create a disk backup which I stored on an external USB drive. Flawless.  Then, I went on to try and create a boot disk, for which I was planning to use a simple USB stick.  No matter what I tried, it just wouldn't work. I originally assumed it was a defective USB device, so I tried creating just an ISO file, and that's just not working.  I see the progress bar going fairly quick, and I then get the message:

Processing...

Preparing to create WinPE image.

Creating WinPE ISO image.

Create WinPE ISO image failed!

Process failed.

Note: when failed to create a bootable USB drive or disc directly, you could see FAQ to solve the problem.

I tried Legacy, I tried UEFI, with and without downloading the WinPE Creating environment, and it just fails.  I do have write access on the destination folder where I was attempting to write the ISO.

If I try to create directly on the USB stick, I get the following similar message:

Note: Do not unplug the USB device during creation.

Processing...

Preparing to create WinPE image.

Creating WinPE ISO image.

Create WinPE ISO image failed!

Process failed.

Note: when failed to create a bootable USB drive or disc directly, you could see FAQ to solve the problem.

Any suggestions?