> but in my next step:  mpiexec -np 4 Imp_win_mpi -in in.crack  I'm facing an error like this 

  Try: mpiexec -np 4 ./Imp_win_mpi -in in.crack

  or: mpiexec -np 4 <FULL PATH TO EXECUTABLE FILE>/Imp_win_mpi -in in.crack where