Mdthbs

I created a virtualbox raw disk pointing to a functioning, booting USB drive with a small linux distro on it.

sudo ./VBoxManage internalcommands createrawvmdk -filename ~/VirtualBox VMs/MyTinyLinux/rawdiskonusb.vmdk -rawdisk /dev/disk2 -partitions 2

When I try to add it to a virtualbox VM, I get this error:

Failed to open the disk image file ~/VirtualBox VMs/MyTinyLinux/rawdiskonusb.vmdk.



Permission problem accessing the file for the medium '~/VirtualBox VMs/MyTinyLinux/rawdiskonusb.vmdk' (VERR_ACCESS_DENIED).



Result Code: VBOX_E_FILE_ERROR (0x80BB0004)

Component: MediumWrap

Interface: IMedium {4afe423b-43e0-e9d0-82e8-ceb307940dda}

Callee: IVirtualBox {0169423f-46b4-cde9-91af-1e9d5b6cd945}

Callee RC: VBOX_E_OBJECT_NOT_FOUND (0x80BB0001)

I saw that the raw disk vmdk file was owned by root. I chown'ed it to my own user.

Still get the same error. I suspect it would work if I ran virtualbox as root, but I really do not want to do that. Is there anyway to make this work?

User should be in a disk group to access raw partitions (as Gilles mentioned by last reference in his answer).

sudo usermod -a -G disk $USER

Check the permission on all the files involved, including the directories: ~/VirtualBox VMs, ~/VirtualBox VMs/MyTinyLinux, ~/VirtualBox VMs/MyTinyLinux/rawdiskonusb.vmdk, /dev/disk2. The directories need to be readable and traversable by your user (chmod +rx) and the image file and the raw disk need to be readable and writable (chmod +rw).

You'll need to allow your user to access the disk; since /dev is populated automatically at each boot, you'll need to add a udev to do this. See Give a specific user permissions to a device without giving access to other users

The poster used linux on the host machine. If you came here and use Windows as a host (like me) there is an easy solution to this error. Windows doesn't allow raw disk access if you don't start VirtualBox with administrator priviledges.

Depending on the distribution, you might have to add your username to the VirtualBox group.

usermod -a -G vboxusers myusername

Additionally, according a similar Q&A on askubunt, you might have a corrupt ISO. In your case, I would guess it means a botched conversion to raw disk. Try searching on how to correctly do that procedure and repeat it, in case the conversion got botched somehow during the first procedure.

If that's still not a solution, then follow the advice in the VirtualBox Manual and add the -relative option:

Creating the image requires read/write access for the given device.
Read/write access is also later needed when using the image from a
virtual machine. If this is not feasible, there is a special variant
for raw partition access (currently only available on Linux hosts)
that avoids having to give the current user access to the entire disk.
To set up such an image, use

VBoxManage internalcommands createrawvmdk -filename /path/to/file.vmdk
-rawdisk /dev/sda -partitions 1,5 -relative

When used from a virtual machine, the image will then refer not to the
entire disk, but only to the individual partitions (in the example
/dev/sda1 and /dev/sda5). As a consequence, read/write access is only
required for the affected partitions, not for the entire disk. During
creation however, read-only access to the entire disk is required to
obtain the partitioning information.

Since there's no accepted answer, I'll post this as an answer for the moment.
In addition to ensuring you're in the right groups, as others have posted above:

sudo usermod -a -G disk $USER

sudo usermod -a -G vboxusers $USER

If you are still getting the VERR_ACCESS_DENIED error, you need to, as per the comment by @Cybex, logout and log back in for the above group additions to take effect.

I had a similar problem but the issue was that I was running the sudo command while in finder I was in my home volume, I cd'd to Volume/Users/Owner where my profile is called owner and then it worked perfectly.