VirtualBox 5.1.18 breaks OSX VMs?
I have been successfully running a variety of OSX VMs (and Windows VMs), including 10.9 Mavericks, under VirtualBox under Windows 8.1 for a long time. Today, when starting up VirtualBox, I was notified of an update from my previous version of VirtualBox to version 5.1.18 and I updated. After doing so, NONE of my OSX VMs will start - the window shows:
and freezes. But it is not just my 10.9 VM - all OSX VMs no longer boot. All my Windows VMs do still boot. I have tried downgrading to VirtualBox 5.1.16 (previous version from early March 2017) with no success and even to 5.1.14 (from January 2017) which I know was working, but also without success.
Is anyone using VirtualBox and has anyone run into this issue?