Inaccessibles virtual machines

[Fielding]

I install some time ago several virtual machines to a friend.

the messages from several virtual machines are :

Runtime error opening 'C:\Users\Luis Yanes\VirtualBox VMs\WindowsXPpro-pdf24\WindowsXPpro-pdf24.vbox' for reading: -103(Path not found.).
F:\tinderbox\win-4.3\src\VBox\Main\src-server\MachineImpl.cpp[731] (long __cdecl Machine::registeredInit(void)).
Código Resultado:
E_FAIL (0x80004005)
Componente:
Machine
Interfaz:
IMachine {480cf695-2d8d-4256-9c7c-cce4184fa048}
Runtime error opening 'C:\Users\Luis Yanes\VirtualBox VMs\WindowsXPpro-aa7\WindowsXPpro-aa7.vbox' for reading: -103(Path not found.).
F:\tinderbox\win-4.3\src\VBox\Main\src-server\MachineImpl.cpp[731] (long __cdecl Machine::registeredInit(void)).
Código Resultado:
E_FAIL (0x80004005)
Componente:
Machine
Interfaz:
IMachine {480cf695-2d8d-4256-9c7c-cce4184fa048}
Runtime error opening 'F:\VirtualBox\Data\WindowsXPpro-SoftwareLuisYanesBello\WindowsXPpro-SoftwareLuisYanesBello.vbox' for reading: -103(Path not found.).
F:\tinderbox\win-4.3\src\VBox\Main\src-server\MachineImpl.cpp[731] (long __cdecl Machine::registeredInit(void)).
Código Resultado:
E_FAIL (0x80004005)
Componente:
Machine
Interfaz:
IMachine {480cf695-2d8d-4256-9c7c-cce4184fa048}
Runtime error opening 'F:\VirtualBox\Data\WindowsXPpro-maquinaluisparamatarseymaspruebas\WindowsXPpro-maquinaluisparamatarseymaspruebas.vbox' for reading: -103(Path not found.).
F:\tinderbox\win-4.3\src\VBox\Main\src-server\MachineImpl.cpp[731] (long __cdecl Machine::registeredInit(void)).
Código Resultado:
E_FAIL (0x80004005)
Componente:
Machine
Interfaz:
IMachine {480cf695-2d8d-4256-9c7c-cce4184fa048}


Must be a configuration file somewhere.
All the virtual machines are in D:


How can I recover ?

Best Regards