Virtualbox resize fixed vdi

C:\Users\dawim\VirtualBox VMs\oracle7-3>VBoxManage.exe clonehd oracle7-3.vdi oracle7-3clone.vdi
0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%
Clone medium created in format 'VDI'. UUID: 82d5d629-aa08-47b6-a6cd-3c319166a093

Release disk and remove from VBox GUI

C:\Users\dawim\VirtualBox VMs\oracle7-3>VBoxManage.exe modifyhd oracle7-3clone.vdi --resize 102400
0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%

C:\Users\dawim\VirtualBox VMs\oracle7-3>VBoxManage.exe clonemedium disk oracle7-3clone.vdi oracle7-3.vdi -variant Fixed
0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%
Clone medium created in format 'VDI'. UUID: 116e5d6a-4655-4def-82fd-536d654b2ab8

Remove temp. image: oracle7-3clone.vdi