Hello! After I increased virtual size of my SIerra 10.12 virtual machine in VirtualBox I need to icrease actual size of my SIerra virtual machine (.vdi file). Nor in the Sierra itself (with disk utility) nor with Gparted utility partition cannot be resized, though there's almost 30 GB unallocated space (as I wrote, I increased virtual size of Sierra) . What should I do to increase partition? Thanks in advance.