go to c:\program files\oracle\virtualbox
important: copy all the files to the virtualbox vdi location
run cmd with administrator in the vdi folder / location, run the command of following:
VBoxmanage.exe modifyhd “Your vdi name.vdi” –resize 25000
eg:
VBoxmanage.exe modifyhd “win7 clone.vdi” –resize 25000
the above command will resize my win7 clone.vdi to 25GB
