Why won't my Windows DISM created ISO image boot?

You are attempting to use an ISO image created with the Windows Deployment Image Servicing and Management (DISM) tool to boot a virtual server, but rather than using the DISM ISO, the virtual server is booting from the native operating system disk.

You used the Windows DISM tool to create an ISO image, then used the Boot from image option to start your virtual server. Your virtual server boots the native operating system disk instead of the DISM ISO as expected.

DISM created ISOs have a "press any key" prompt which requires intervention at the KVM for the ISO to be booted. If you do not press a key within 5 seconds, the virtual server boots the normal operating system, bypassing the ISO.

You can remove the "press any key" prompt from a DISM created ISO by completing the following steps:

1. Open the ISO with an ISO editing application, for example, PowerISO, UltraISO, etc.
2. Delete bootfix.bin.
3. Replace EFISYS.BIN with efisys_noprompt.bin. You can find efisys_noprompt.bin on most Windows installations by searching.
4. Save the ISO.
5. Upload the modified ISO to IBM Cloud® Object Storage, and then import the image from IBM Cloud Object Storage. For more information, see Preparing and importing images.
6. Try the Boot from an image task again.