--- loncom/interface/londocs.pm	2016/11/23 01:28:50	1.612
+++ loncom/interface/londocs.pm	2016/11/23 16:42:25	1.613
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # Documents
 #
-# $Id: londocs.pm,v 1.612 2016/11/23 01:28:50 raeburn Exp $
+# $Id: londocs.pm,v 1.613 2016/11/23 16:42:25 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -3951,6 +3951,9 @@ END
                 my $shownurl = &Apache::lonenc::encrypted($url);
                 if (&Apache::lonnet::symbverify($shownsymb,$shownurl)) {
                     $url = $shownurl.(($shownurl=~/\?/)?'&':'?').'symb='.&HTML::Entities::encode($shownsymb,'"<>&');
+                    if ($env{'request.enc'} ne '') {
+                        delete($env{'request.enc'});
+                    }
                 } else {
                     $url='';
                 }