virtualbox.org

I had a working VM for MAcOSX (10.15). I use it mostly for doing Mac software dev from my Win10 dev system.

I hadn't started the Mac VM for a while (a year or so). This week I ran the VirtualBox host, intending to start that Mac VM (so I could do a Mac build of some cross-platform software I wrote). When I ran VirtualBox, it said that there was a new version that I should upgrade to. I ran the install for the new version. I then restarted VirtualBox, and tried to start my Mac OSX VM. It will no longer boot properly.

Did the new version of VirtualBox break something with Mac OSX VMs?

Windows host OS running a Mac guest is only allowed if the physical computer is real Mac hardware.
OSX guests on non-Apple hardware

If you really do have a Mac computer, please start a new topic in the Mac Guests subform, with a zipped guest vbox.log, posted using the forum's Upload Attachment tab.