How To Enlarge a Virtual Machine’s Disk in VirtualBox
When you create a virtual hard disk in VirtualBox you specify a maximum disk size. If you want more space on your virtual machine’s hard disk later, you’ll have to enlarge the virtual hard disk and partition.
Note that you may want to back up your virtual hard disk file before performing these operations – there’s always a chance something can go wrong, so it’s always good to have backups. However, the process worked fine for us.
Enlarge a Virtual Disk in VirtualBox
To enlarge a virtual disk in VirtualBox, you’ll need to use the VBoxManage command from a Command Prompt window. First, shut down the virtual machine – ensure its state is set to Powered Off, not Saved.
Second, open a Command Prompt window from your Start menu and change to VirtualBox’s program files folder so you can run the command:
cd “C:\Program Files\Oracle\VirtualBox”
The following command will operate on the VirtualBox virtual disk located at “C:\Users\Chris\VirtualBox VMs\Windows 7\Windows 7.vdi”. It will resize the virtual disk to 81920 MB (80 GB).
VBoxManage modifyhd “C:\Users\Chris\VirtualBox VMs\Windows 7\Windows 7.vdi” --resize 81920
(Use two dashes before resize in the command above.)
Replace the file path in the command above with the location of the VirtualBox disk you want to resize and the number with the size you want to enlarge the image to (in MB).
Note that this process doesn’t enlarge the partition on the virtual hard disk, so you won’t have access to the new space yet – see the Enlarge the Virtual Machine’s Partition section below for more information.