VERR_VD_IMAGE_CORRUPTED / NS_ERROR_FAILURE

[J.Bird]

Hi, I'm currently having problems running Virtual Box 5.1.14 (pretty sure its r112924 (Qt5.6.2)) from a backup external hard drive with Windows 10 (64-bit) on my MacBook Pro (13-inch, Mid 2012) with OS X El Capitan Version 10.11.6 and 2.9 GHz Intel Core i7 processor. I'm fairly new to VirtualBox and have only had it for about a month. I'm currently only using it to run ORCAD PSpice (student version). Today, I finally downloaded Windows 10 Education with a product key to officially activate windows. It was successful and I left my laptop for a while. I come back to find my computer had to shut down while I was away and from then on today I have been unable to run VirtualBox. This is my error message:

Failed to open a session for the virtual machine Windows 10.
Could not open the medium '/Volumes/My Passport/Windows 10/Windows 10.vhd'.
VD: Image file '/Volumes/My Passport/Windows 10/Windows 10.vhd' is corrupted and can't be opened (VERR_VD_IMAGE_CORRUPTED).

Result Code: NS_ERROR_FAILURE (0x80004005)
Component: MediumWrap
Interface: IMedium {4afe423b-43e0-e9d0-82e8-ceb307940dda}

Any and all help is much appreciated!

[socratis]

is corrupted and can't be opened

I suggest starting afresh. The error is clear. The file was corrupted during shutdown. It was on an external HD after all and that's not something unheard of; external HD files going corrupt after a sudden shutdown.

Today, I finally...

You have to lose about a day's work. Not that much for a really important lesson like that, if you ask me. If you don't want a repeat of this, there are several things you should/could do:

• Backup your user files somewhere outside the VM, like you would do with a normal computer.
• Use another external HD to make a backup of the VM itself. See "Moving a VM" and interpret it as "Backing up a VM".
• Don't leave your computer unattended while a live filesystem is running off an external HD.
• Change the policies of your host regarding power policies, i.e. shutdown when at 5% of the battery.
• Change the policies of your guest regarding power policies, i.e. shutdown when at 15% of the battery.

[mpack]

To which I would add: stop using VHD. It is prone to this kind of failure, which I would guess was caused by unplugging the external drive before the files were closed.

There is no well regarded VM platform which currently uses VHD as its primary format, add to which I certainly don't understand why you'd choose it on an OS X host!