Refer to pages 37-42 of the User Manual (it's in /opt/VirtualBox/UserManual.pdf).

You install VirtualBox as root, you install one or more virtual machines as "you." The installer checks for the group vboxusers and, if it does not exist, the installer creates it but you must add your username to the group manually (you only do this once, installing an updated version of VirtualBox will not overwrite the group entry).

You install virtual machines as "you," not as root. By default, virtual machines are added in your home directory tree. You can create a partition on your hard drive or on a separate disk drive and install your virtual machines there.

For example, I have a partition /var/lib/virtual where virtual machines live. I only have one install at this time and it's Win7. The tree looks like this:
The mount point, virtual, has this permission mask
That is,
so I can read and write to it.

The content of /var/lib/virtual looks like
Note that the directory HardDisks is no longer used by VirtualBox and, because it's a partition, there is a lost+found directory (you won't have lost+found in your home directory). I just leave the directory there, there's nothing in it

Now, I own all the directories and files in the Machines directory and the group is users. That's normal. What gives me permission to write is the parent directory, /var/lib/virtual which is owned by root, group vboxusers and the mode 775. That's automatically done by VirtualBox when, as you, you create a virtual machine. Keep in mind that this tree is on a separate partition, not in my home directory. Look at the tree that was created in your home directory and see what it looks like, particularly what the root directory of the virtual machine looks like (it'll be in your home and its group should be vboxusers). That's not your home directory, it's the directory VirtualBox created when you added a virtual machine in your home directory (and I don't remember what it's named, you'll need to look, it might be a dot-directory). I haven't ever created a virtual machine in my home directory, so I'm at a loss here about the tree structure when you do that.

Be sure to take a little time and scan through the User Manual.

Hope this helps some.

4 members found this post helpful.

This what makes me thing its a Slackware specific config because following their (VirtualBox) manual does not work. I add my user to the group as documented but virtualbox won't even start so I haven't even created any guests yet or told it where I want to put them. Unless I do logoff and back in as root then run it and it works fine.

Well, no, it's not Slackware-specific: if you installed VirtualBox by, as root, executing, for example the 64-bit VirtualBox-4.3.26-98988-Linux_amd64.run and did not get any errors, you should be good to go. That install file is from https://www.virtualbox.org/wiki/Linux_Downloads All Distributions (pick i386 or AMD64 depending on your system).

You will not be able to execute VirtualBox logged in as "you' until you've added your user account name to vboxuser with, as root
Now, you do need to check /etc/group and make sure that you have one line similar to this one:
where username is your user name.

Then, you can start VirtualBox (not as root) and install the Extension Pack from the link on the Downloads page (https://www.virtualbox.org/wiki/Downloads -- up one from the VirtualBox 4.3.26 for Linux page).. You want the All Supported Platforms link. You really do want the Extension Pack (for USB support and other Good Things).

You do not want to run VirtualBox as root, you want to run it as "you." Things will get really, really screwy if you run it as root or install a virtual machine as root. You do not want to establish a user account for vboxusers. You can, if you like create a user account for using VirtualBox (that means log off as you, log on as that user... but why? It's supposed to be used by you.)

When you start VirtualBox you'll have the VirtualBox Manager window displayed (that's where you install the Extension Pack). From there you can create one or more virtual machines (guests). If you're going to install, say, Win7, one of the things you'll do is allocate disk for it -- the suggested default disk size for Win7 is 25G. Don't use less if you actually are going to use it. Save yourself a lot of trouble and fooling around by giving it a lot more space than just a base install.

If you've started VirtualBox as root, you've probably got the local (in your home directory) tree owned by root. Check that and change it to your username so you can read and write to it. The default directory (in your home directory) is VirtualBox\ VMs (that's how it appears when you use ls; it's because of the space character).

Hope this helps some.

3 members found this post helpful.

So those are the exact steps I did this time as well as the past. Download from my account and make executable. Su - root and install, add my user to the vboxusers group. Then when I try to run virtualbox as myself it throws the error that I'm not running it as root. This always worked before but now doesn't