diff --git a/examples/COUPLE/plugin/liblammpsplugin.c b/examples/COUPLE/plugin/liblammpsplugin.c
index 09912448d7..996a27524f 100644
--- a/examples/COUPLE/plugin/liblammpsplugin.c
+++ b/examples/COUPLE/plugin/liblammpsplugin.c
@@ -67,7 +67,10 @@ liblammpsplugin_t *liblammpsplugin_load(const char *lib)
 
 #if defined(LAMMPS_LIB_MPI)
   ADDSYM(open);
+#else
+  lmp->open = NULL;
 #endif
+
   ADDSYM(open_no_mpi);
   ADDSYM(open_fortran);
   ADDSYM(close);
diff --git a/examples/COUPLE/plugin/liblammpsplugin.h b/examples/COUPLE/plugin/liblammpsplugin.h
index 0fc993fca8..0865be6bb9 100644
--- a/examples/COUPLE/plugin/liblammpsplugin.h
+++ b/examples/COUPLE/plugin/liblammpsplugin.h
@@ -111,6 +111,8 @@ struct _liblammpsplugin {
   void *handle;
 #if defined(LAMMPS_LIB_MPI)
   void *(*open)(int, char **, MPI_Comm, void **);
+#else
+  void *open;
 #endif
   void *(*open_no_mpi)(int, char **, void **);
   void *(*open_fortran)(int, char **, void **, int);
diff --git a/examples/COUPLE/plugin/simple.c b/examples/COUPLE/plugin/simple.c
index 1401a22f49..0ca5726072 100644
--- a/examples/COUPLE/plugin/simple.c
+++ b/examples/COUPLE/plugin/simple.c
@@ -93,7 +93,13 @@ int main(int narg, char **arg)
       MPI_Abort(MPI_COMM_WORLD,1);
     }
   }
-  if (lammps == 1) lmp = plugin->open(0,NULL,comm_lammps,NULL);
+  if (lammps == 1) {
+    if (plugin->open == NULL) {
+      printf("ERROR: liblammpsmpi.c must be compiled with -DLAMMPS_LIB_MPI=1 for this program\n");
+      MPI_Abort(MPI_COMM_WORLD,2);
+    }
+    lmp = plugin->open(0,NULL,comm_lammps,NULL);
+  }
 
   while (1) {
     if (me == 0) {