Hi all, I had posted a thread before about getting a "too many communicators" error after a long run. After going through with totalview i didn't see any problems. I am using Hypre in MPI as a Poission solver. I think this is probably causing the error because i need to create and destroy multiple Hypre solver constructs during my run (at almost every iteration) . Does anyone know enough about Hypre coupled with MPICH to know if Hypre frees all the communicators when it destroys the constructs? I looked over the hypre message board but it's pretty dead, i was wondering if i'll have better luck here. Ryan Crocker University of Vermont, School of Engineering Mechanical Engineering Department