diff --git a/library/Icinga/Application/Modules/Module.php b/library/Icinga/Application/Modules/Module.php
index f07f34908..52b283829 100644
--- a/library/Icinga/Application/Modules/Module.php
+++ b/library/Icinga/Application/Modules/Module.php
@@ -528,7 +528,9 @@ class Module
     {
         $this->launchConfigScript();
         $files = $this->cssFiles;
-        $files[] = $this->getCssFilename();
+        if (file_exists($this->getCssFilename())) {
+            $files[] = $this->getCssFilename();
+        }
         return $files;
     }