VBoxManage list vms lists all registered virtual machines (running or otherwise) C:\> VBoxManage list vms
"Win10Pro afterInstalling" {1a2b86d3-7e81-45d8-b541-caf582c6c9f8}
"<inaccessible>" {fd2449c2-c0d4-4d64-8fd2-c0ad86502c36}
"Windows10" {6c0d543f-c5af-47c7-afbb-9a941e455c9b}