The command cmd can call MPI execmpi.exe
or FreeFem+±mpi .exe(but there is a width default ffglut: ffglut .exe),
respectively, but calling the latter with the former （“Program Files\Microsoft MPI\Bin\mpiexec.exe” -n 4 C:>“Program Files (x86)\FreeFem++\FreeFem+±mpi.exe”) will fail to access.
