I deleted two virtual disks from a VirtualBox VM the wrong way. I removed them from the guest config, but forgot to remove them from the media list, and deleted the files and directories from the filesystem, so I see the disks as errored in the media list. They have associated snapshots, so I get errors about them being in use. If I try to delete the associated snapshots via the GUI or `vboxmanage` I get this error message: 

```none
VBoxManage.exe: error: VD: error VERR_PATH_NOT_FOUND opening image file [location]

```

Of course the snapshots are also gone (these were old vmdk files I mounted, so the snapshots may not even be real). How do I manually remove these ghost entries from my VirtualBox config? I suspect there's a config file or a registry entry, but I'm not sure where to look.