diff --git a/lib/files/mapper.php b/lib/files/mapper.php
index c5f1f9888dbce11ab7c22eb2909787db040e8e9c..418ef354f9c85e26966daf29daa7195c0523d1b4 100644
--- a/lib/files/mapper.php
+++ b/lib/files/mapper.php
@@ -219,10 +219,8 @@ class Mapper
 		// remove unwanted characters
 		$text = preg_replace('~[^-\w]+~', '', $text);
 
-		if (empty($text))
-		{
-			// TODO: we better generate a guid in this case
-			return 'n-a';
+		if (empty($text)) {
+			return uniqid();
 		}
 
 		return $text;