diff --git a/tos/lib/net/rpl/RPLOF0P.nc b/tos/lib/net/rpl/RPLOF0P.nc
index b95b96b1a5..94dad68fc9 100644
--- a/tos/lib/net/rpl/RPLOF0P.nc
+++ b/tos/lib/net/rpl/RPLOF0P.nc
@@ -134,15 +134,12 @@ implementation{
 
     parentNode = call ParentTable.get(min);
 
-    while ((!parentNode->valid) &&
-           (min < MAX_PARENT) &&
-           (parentNode->rank != INFINITE_RANK)) {
-      min++;
+    while ((min < MAX_PARENT) &&
+           ((!parentNode->valid) || (parentNode->rank == INFINITE_RANK))) {
+      min++; // skipping invalid entries and nodes with infinite rank
       parentNode = call ParentTable.get(min);
     }
 
-    minDesired = parentNode->etx_hop + (parentNode->rank * divideRank);
-
     if (min == MAX_PARENT) {
       call RPLOF.resetRank();
       call RPLRoute.inconsistency();
@@ -151,6 +148,8 @@ implementation{
       return FALSE;
     }
 
+    minDesired = parentNode->etx_hop + (parentNode->rank * divideRank);
+
 //     printf("RPLOF: Start Compare %d %d: %d %d %d \n",
 //            htons(prevParent), htons(parentNode->parentIP.s6_addr16[7]),
 //            minDesired, parentNode->etx_hop, parentNode->rank);