Assuming you use the official Ubuntu packages:
> mpicc: error while loading shared libraries: libopen-pal.so.0: cannot
> open shared object file: No such file or dir
The library should exist under /usr/lib/libopen-pal.so.0 (which symlinks
to /usr/lib/libopen-pal.so.0.0.0 which symlinks to the real position
Is it there? If not, then you need to install the openMPI shared
libraries (the package is called libopenmpi1).