virtualbox.org

Hi All,

I'm a total novice when it comes to VirtualBox and have hit a show-stopping problem trying to install Mac OS X 10.11 (El Capitan) as a guest OS. I'm running VirtualBox 5.2.22 r126460 (Qt5.6.3) on macOS 10.14.1 (Mojave). I'm doing this as I have some older OS X software that is not compatible with Mojave and won't be updated by the developer. I'm hoping that there is something very simple I'm doing wrong and someone can tell me what!

I created an OS X virtual machine in VirtualBox, with a new .vdi as the virtual hard drive, and attached the installESD.dmg (from my El Capitan installer USB drive) to the virtual optical drive. The problem I have is that when I run the virtual machine, it just boots to the EFI console and shows no file systems, just BLK0 and BLK1. In other words, I've failed at pretty much the first step!

I have also tried converting the .dmg to a .iso, but that doesn't work either (same problem - boots to EFI console which shows no filesystems). The .dmg mounts just fine in macOS so I don't think there's a problem with the .dmg file itself.

Any help much appreciated!!

Well...

Turns out the method I used before to create the ISO must have gone wrong somewhere - I just used socratis' script (can't post link as I'm a noob, but it's on this forum at: viewtopic.php?f=22&t=81443) instead, and I'm now installing 10.11 in my VirtualMachine!

Does anyone know why booting from the .dmg didn't work? I thought that was supposed to be possible in the latest VirtualBox?

Dr. H wrote:Does anyone know why booting from the .dmg didn't work?

Because the DMG is not bootable. Just because you have a collection of files, that doesn't mean that this collection is bootable. It takes special "magic" (format/structure) to make an image bootable, and the InstallESD.dmg doesn't have the proper format/structure to make it bootable.

Glad I could help with the script. Marking as [Solved].

socratis wrote:

Dr. H wrote:Does anyone know why booting from the .dmg didn't work?

Because the DMG is not bootable.

Good point! Sorry to have troubled you with my noob issues! Hopefully this post will be helpful to others in the future...