to remove permanently an HDD from the VirtualBox Media Manager and from the disk there are this set of commands from Linux:
vboxmanage list hdds
UUID: c451287d-4cee-4c6f-bcc1-8fbacadceb53
Parent UUID: base
State: created
Type: normal (base)
Location: /home/glitch/SSDvms/LX/LIBRENMS/LIBRENMS.vdi
Storage format: VDI
Capacity: 102400 MBytes
Encryption: disabled
Detach the disk from VM
vboxmanage closemedium disk c451287d-4cee-4c6f-bcc1-8fbacadceb53 --delete
0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%Ok, now you can recreate a new HDD with same filename!
.glitchlist crew