--- loncom/interface/lonhelp.pm	2004/01/15 03:18:19	1.14
+++ loncom/interface/lonhelp.pm	2004/05/17 22:08:56	1.15
@@ -101,7 +101,11 @@ sub render
     # LaTeX .aux files
     # absolute paths for use with help.loncapa.org
     $tex =~ s|  \\ref\{([^}]*)\}
-             |'\\begin{html}<a href="http://' . $serverroot ."/adm/help/".
+             |
+              if (not(exists($fragmentLabels{$1}))) {
+	          &Apache::lonnet::logthis("ERROR: $1 not a valid help label");
+              };
+             '\\begin{html}<a href="http://' . $serverroot ."/adm/help/".
               substr($fragmentLabels{$1}, 0, -4) .
               '.hlp#' . processLabelName($1) . 
              '"><img src="http://' . $serverroot . '/adm/help/gif/smallHelp.gif" border="0" /></a>' .