Hi gretl Masters (Allin and Jack), I think this message is targeted to Jack. I discovered that to enable MPI we must set the environment var MPICC. In the guide gretl-mpi.pdf (page 9), you must change ".. can also..." : (original) Once MPI is installed it should probably be found automatically by gretl’s configure script. If need be you can give the process some help. For instance, if Open MPI is installed under /opt/openmpi you might do --with-mpi-lib=/opt/openmpi/lib --with-mpi-include=/opt/openmpi/include (see ./configure --help). You can also set the path to the MPI compiler-wrapper, mpicc, via the environment variable MPICC, as in MPICC=/opt/openmpi/bin/mpicc ./configure ... (proposed corrected) Once MPI is installed it should probably be found automatically by gretl’s configure script. If need be you can give the process some help. For instance, if Open MPI is installed under /opt/openmpi you might do --with-mpi-lib=/opt/openmpi/lib --with-mpi-include=/opt/openmpi/include (see ./configure --help). You must also set the path to the MPI compiler-wrapper, mpicc, via the environment variable MPICC, as in MPICC=/opt/openmpi/bin/mpicc ./configure ... It's a MUST and not an optional thing! This is my successful build command: MPICC=/usr/lib64/openmpi/bin/mpicc ./configure --enable-build-doc --with-gsf --with-mpi --with-mpi-lib=/usr/lib64/openmpi --with-mpi-include=/usr/include/openmpi-x86_64 --with-odbc --with-libR --enable-quiet-build --enable-build-addons ---- I am again without working project (==job), I am wiling to relocate if there is some project where I can contribute with my IT knowledge. Please contact me for more details. Thanks.