diff --git a/api/src/Cache/Files.php b/api/src/Cache/Files.php
index ee802ab7e8..ff30254672 100644
--- a/api/src/Cache/Files.php
+++ b/api/src/Cache/Files.php
@@ -207,7 +207,7 @@ class Files extends Base implements Provider
 	 */
 	function filename(array $keys,$mkdir=false)
 	{
-		$fname = $this->base_path.'/'.str_replace(array(':','*'),'-',implode('/',$keys));
+		$fname = $this->base_path.'/'.str_replace(array(':','*','\\'),'-',implode('/',$keys));
 
 		if ($mkdir && !file_exists($dirname=dirname($fname)))
 		{