This happens regardless of boot order (CD or HD first), regardless of the type of virtual optical controller. Pressing F12 at the splash screen and selecting CD or HD yields the exact same result. I've tried it with the .DMG pulled from a Yosemite, Mavericks, and Mt. Lion install package; all with the same result. I've also tried several online tutorials for turning the DMG into an ISO and a bootable ISO; and all manner of craziness. Although I also read that VB 4.3x supports the factory DMGs as bootable media. So far "nothing" has worked.
Interestingly, several months back when running Mt.Lion as the host machine, I was able to install 10.8.5 just fine, then eventually update the guest to 10.9 and 10.10 which worked fine. But now I'm trying to do a fresh install of 10.10 on the guest and having zero luck.
[update] For what it's worth, if I use a Windows 7x32 .iso, the same VB boots perfectly fine
[update2] I used Diskmaker X to create a 'bootable' .dmg from the 10.10 installer; no luck. Then I used Disk Utility to convert the DMG into CDR; no luck. Renamed the CDR to ISO; no luck.
Host: 10.10.2
VB: 4.3.26 r98988
Would love any help, thanks!
See attachment for VB settings screenshot