This is an original Core Protocol command.

This command is used to logically disconnect client access to a server resource. The resource sharing connection is identified by the TID in the SMB Header (section, and the TID is invalidated. It MUST NOT be recognized if used by the client in subsequent requests. All open files, directories, and other resources that exist within the resource identified by the TID are released. Locks on files or directories within the shared resource are also released.