I am programming in MPI over LAN and I have to use the job submit command line, the command is this:
job submit /numnodes:2 /workdir:\\\\%computername%\\test
I assume from your tag that you're using MPICH and from your question that you're using Windows HPC Server. While I know nothing about Windows HPC Server, I do know about MPICH, and MPICH doesn't support Windows anymore. You might try using Microsoft's own MPI implementation, MS-MPI. It's free to use and will probably integrate with their environment much better.