[Solved] FATAL: Could not read from the boot medium! System Halted!

[Hoggio]

Hi

I just wanted to say thank you for all your help. I am now fully back up and running.

I've also increased the RAM which, as you would expect, has speeded things up.

Had a bit of a glitch where one piece of software failed to start and kept giving an error notice but that has now been solved too.

Thanks again. Much appreciated.

[socratis]

Nice! Glad you're up and running.
I'm going to go ahead and mark this as [Solved].

[bbender-v]

Hey socratis,

I wanted to post a "me too", I think I saw something similar after upgrading to 5.1.18 (from 5.1.16) on ElCap 10.11.6: I have a Linux VM that I've been using for a really long time, and 5.1.18 pretty much wiped clean the VM config. By the time I figured out what had happened, the .vbox-prev had been overwritten too, and I haven't been able to get the original pre-5.1.18 .vbox version back (I have an offline backup, but I refreshed it after the last time I shut it down, and the .vbox and -prev were apparently already rewritten at that point.

Initially, the symptom I noticed was the same message as the OP: "FATAL: Could not read from the boot medium! Sysytem Halted". What I eventually found was that the VM had been reset back to a generic state -- 128MB RAM, 8MB VRAM, no storage devices, no network devices, no USB, no I/O APIC, single CPU (the OS type was still correctly set to "Other Linux (64-bit)"). The disk was still there, and I was able to recreate the machine around it. The only thing I really lost was some snapshot states.

But I just wanted to throw this out as a data point -- seems like there's some kind of corner case in the .vbox handling in 5.1.18. I'll keep trying catch it (I have some other old VMs, I'll make sure I have offline copies before I touch them).

[socratis]

I'm not sure that this thread was talking about a corrupt .vbox file, but then on the other hand it was never discussed orexcluded. I would suggest to continue this in a new thread if you think that this is indeed a problem. Especially if this thread is already marked as solved. I also have to mention I've haven't heard of any 5.1.18 related .vbox corruption.