diff --git a/app/dexter.pl b/app/dexter.pl
index efdb21a..45b2fd1 100755
--- a/app/dexter.pl
+++ b/app/dexter.pl
@@ -28,6 +28,7 @@ Readonly::Hash my %MEANING_OF_HTTP_CODE => (
     '404' => 'File Not Found',
     '409' => 'Conflict',
     '413' => 'Payload Too Large',
+    '500' => 'Internal Server Error',
 );
 
 Readonly my $ROOT_DIRECTORY   => 'public';
@@ -119,7 +120,19 @@ helper render_index => sub ($c) {
     my $url  = $c->req->url;
     my $user = $c->req->env->{REMOTE_USER};
     my $path = $url->path;
-    
+
+    if ( not -r $ROOT_DIRECTORY . $path->to_route ) {
+        $path->trailing_slash(0);
+        $path = $path->to_dir;
+        $url->path($path);
+
+        $c->render(template => 'error',
+                    status  => '500',
+                    message => 'Dexter cannot read that file or index!');
+
+        return 0;
+    }
+
     if ( not -d $ROOT_DIRECTORY . $path->to_route ) {
         $path->trailing_slash(0);
         $path = $path->to_dir;