vboxmanage showvminfo Win7x64VM | grep UUID

UUID: 128d891a-be8b-4c03-ba53-9acf1940a6c1
Hardware UUID: 128d891a-be8b-4c03-ba53-9acf1940a6c1

vboxmanage modifyvm “Win7x64VM Clone” –hardwareuuid “{128d891a-be8b-4c03-ba53-9acf1940a6c1}”