Multiple WMC instances can run at a time, all will be accessible to a client. Any UPnP AV client can be used to access WMC shared media. The client can query WMC for the list of files shared, the result of the query is formatted using XML.
Multiple instances of WMC can operate concurrently, all accessible to a client. Any UPnP AV client can be used to access shared media from WMC. The client can request the list of files shared by WMC, and the response is formatted using XML.