/Type=ShadowType /Provider=ProviderNameOrId /For=ForVolumeSpec /Shadow=ShadowId|/Set=ShadowSetId - Displays existing shadow ...

%1 %2 [/Type=ShadowType] [/Provider=ProviderNameOrId] 
    [/For=ForVolumeSpec] [/Shadow=ShadowId|/Set=ShadowSetId]
    - Displays existing shadow copies on the system.  Without any options, 
    all shadow copies on the system are displayed ordered by shadow copy set.  
    Any combinations of options are allowed to refine the list operation.  
    - The Shadow Copy ID can be obtained by using the List Shadows command.
      The Provider ID can be obtained by using the List Providers command.
    When entering a Provider, Shadow, or Shadow Set ID, it must be in 
    the following format:
       {XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX} 
    where the X's are hexadecimal characters.  

    Example Usage:  vssadmin List Shadows /Type=ClientAccessible 
                            /Provider={b5946137-7b9f-4925-af80-51abd60b20d5}
                            /Shadow={c5946237-af12-3f23-af80-51aadb3b20d5}
    - Valid shadow copy types: