Index: accessible_content.module
===================================================================
--- accessible_content.module	(revision 8684)
+++ accessible_content.module	(working copy)
@@ -841,21 +841,27 @@
   foreach ($themes[$current_theme]->stylesheets as $media => $theme_stylesheet) {
     if ($media == 'screen' || $media == 'all') {
       foreach ($theme_stylesheet as $sheet) {
-        $css[] = $base_url .'/'. $sheet;
+        if(file_exists($sheet)) {
+          $css[] = $base_url .'/'. $sheet;
+        }
       }
     }
   }
   if (is_array($css_files['all']['module'])) {
     foreach ($css_files['all']['module'] as $path => $enabled) {
       if ($enabled) {
-        $css[] = $base_url .'/'. $path;
+        if(file_exists($path)) {
+          $css[] = $base_url .'/'. $path;
+        }
       }
     }
   }
   if (is_array($css_files['all']['theme'])) {
     foreach ($css_files['all']['theme'] as $path => $enabled) {
       if ($enabled) {
-        $css[] = $base_url .'/'. $path;
+        if(file_exists($path)) {
+          $css[] = $base_url .'/'. $path;
+        }
       }
     }
   }