VirtualBox error NS_ERROR_INVALID_ARG (0X80070057) when adding an existing virtual machine

If you've ever encountered the following error when adding an existing VM to your host:

Failed to open virtual machine located in *********.vbox.
Callee RC: NS_ERROR_INVALID_ARG (0X80070057)

or from the commandline  VBoxManage registervm VirtualMachineNameSample.vbox

VBoxManage: error: Code NS_ERROR_INVALID_ARG (0x80070057) - Invalid argument value (extended info not available)
VBoxManage: error: Context: "OpenMachine(Bstr(szVMFileAbs).raw(), Bstr(strPassword).raw(), machine.asOutParam())" at line 153 of file VBoxManageMisc.cpp

One thing that you can check is see if there's a non-existing file. In my case, the solution is to edit the .vbox file manually (which is in XML format) and remove the following line:

      <DVDImages>
        <Image uuid="{a82fec76-40db-4b60-9054-4fd156c8982a}" location="/usr/share/virtualbox/VBoxGuestAdditions.iso"/>
      </DVDImages>

Some people say that it could also because of insufficient disk space. In my case, there was plenty of space, but this file no longer exists since it's from a different machine.