virtualbox.org

I am using 4.2 and trying to change medium type from normal to shareable and getting the following error.

Error changing medium type from Normal to Shareable.

Cannot change type for medium 'C:\Users\jruiz5\VirtualBox VMs\Oracle Server\Oracle Server-disk2.vdi' since it has 1 child media.

Result Code: VBOX_E_OBJECT_IN_USE (0x80BB000C)
Component: Medium
Interface: IMedium {29989373-b111-4654-8493-2e1176cba890}