OpenMPI-bin error after update (K)Ubuntu 18.04 to 20.04
First remove the update-alternatives for openmpi: sudo rm -f /etc/alternatives/mpi* /var/lib/dpkg/alternatives/mpi* Then install openmpi-bin again: sudo apt install open-mpi answer Y when asked for confirmation. In Ubuntu 22.04 (or if the above line doesn’t work) – try this instead: sudo apt install openmpi-bin