1. A virtual processor system comprising: a plurality of processor to execute processes in parallel including respective virtual processors and storing a plurality of logical processor numbers corresponding to destination processors of said plurality of processors; main storage means, associated with said plurality of processors for storing data and system information; and transfer processing means for transferring said data and system information among said plurality of processors by selecting a destination logical processor number of said plurality of logical processor numbers corresponding to a processor and a respective virtual processor of said plurality of processors, reading said data and system information from said main storage together with said processor and said respective virtual processor corresponding to said selected destination logical processor number and transferring said read data and system information to at least one of said processor and said respective virtual processor; wherein said transfer processing means associates said destination logical processor number with a physical processor valid flag, and when said physical processor valid flag indicates an invalid state, cancels communication of data designating the processor and, when said physical processor valid flag indicates a valid state, starts communication of data designating the processor.