--- loncom/interface/lonnavmaps.pm	2016/03/02 20:07:20	1.516
+++ loncom/interface/lonnavmaps.pm	2016/03/17 13:20:35	1.517
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Navigate Maps Handler
 #
-# $Id: lonnavmaps.pm,v 1.516 2016/03/02 20:07:20 raeburn Exp $
+# $Id: lonnavmaps.pm,v 1.517 2016/03/17 13:20:35 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -2768,11 +2768,13 @@ sub parmval_real {
 sub recurseup_maps {
     my ($self,$mapname) = @_;
     my @recurseup;
-    my @pcs = split(/,/,$self->getResourceByUrl(&Apache::lonnet::clutter($mapname))->map_hierarchy());
-    shift(@pcs);
-    pop(@pcs);
-    if (@pcs) {
-        @recurseup = map { &Apache::lonnet::declutter($self->getByMapPc($_)->src()); } reverse(@pcs);
+    if ($mapname) {
+        my @pcs = split(/,/,$self->getResourceByUrl(&Apache::lonnet::clutter($mapname))->map_hierarchy());
+        shift(@pcs);
+        pop(@pcs);
+        if (@pcs) {
+            @recurseup = map { &Apache::lonnet::declutter($self->getByMapPc($_)->src()); } reverse(@pcs);
+        }
     }
     return @recurseup;
 }