--- loncom/interface/lonmenu.pm	2019/08/06 14:44:36	1.497
+++ loncom/interface/lonmenu.pm	2019/08/06 15:54:37	1.498
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Routines to control the menu
 #
-# $Id: lonmenu.pm,v 1.497 2019/08/06 14:44:36 raeburn Exp $
+# $Id: lonmenu.pm,v 1.498 2019/08/06 15:54:37 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -450,6 +450,7 @@ sub secondary_menu {
         }
         if ($env{'request.course.groups'} ne '') {
             foreach my $group (split(/:/,$env{'request.course.groups'}) {
+                next unless ($group =~ /^\w+$/);
                 my @privs = split(/:/,$env{"user.priv.$env{'request.role'}./$cdom/$cnum/$group"});
                 shift(@privs);
                 if (@privs) {