@JonB In command line, we usually kill a mpi program by killing one of the child processes. And I find this may be a bug of intel mpi on windows [ https://community.intel.com/t5/Intel-oneAPI-HPC-Toolkit/InteloneAPI-MPI-2021-2-0-behavior-on-Linux-and-Windows-differ/td-p/1290020 ]. Anyway, thanks for your reply.