I have been trying to convert the Dynamically sized hard drive to a fixed size to increase the VM box performance. I tried to follow the instruction on Convert Dynamically Sized VirtualBox VDI Hard Drive to Fixed Size

But I keep running into an issue when trying to manually remove the old drive Here is the command that I am trying to use

vboxmanage closemedium disk "3f883a9e-037a-4f67-8ed4-f82ea2c7a84b" –delete

Which gives me this error

c:\Program Files\Oracle\VirtualBox>vboxmanage closemedium disk "3f883a9e-037a-4f 67-8ed4-f82ea2c7a84b" VBoxManage.exe: error: Medium 'C:\Users\malhayek\VirtualBox VMs\settler_default_ 1434987271004_24349_1438813340021_48330\box-disk1.vmdk' cannot be closed because it is still attached to 1 virtual machines VBoxManage.exe: error: Details: code VBOX_E_OBJECT_IN_USE (0x80bb000c), componen t MediumWrap, interface IMedium, callee IUnknown VBoxManage.exe: error: Context: "Close()" at line 1551 of file VBoxManageDisk.cpp

What can I do to correctly set the hard drive size to Fixed?

  • Is that disk currently part of a virtual machine? It seems like that's what is happening here, check all your VM's and if you find the one using that disk, shut it down and remove the disk from it then try the closemedium command again.
    – Aaron Tate
    Commented Aug 6, 2015 at 2:17

1 Answer 1


The error itself is about the fact that you cannot delete an harddrive if it's still attached to a VM, so you should remove it as reported in the article:

Open the virtual box manager, go to settings for your machine and remove the old (dynamically sized) drive from the SATA controller for this machine.

Important: as the article itself says, be careful and make sure you have a backup.

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