diff --git a/apps/dav/lib/Connector/Sabre/File.php b/apps/dav/lib/Connector/Sabre/File.php
index a7a2470b4f..4e45661605 100644
--- a/apps/dav/lib/Connector/Sabre/File.php
+++ b/apps/dav/lib/Connector/Sabre/File.php
@@ -676,6 +676,8 @@ class File extends Node implements IFile {
 	}
 
 	protected function header($string) {
-		\header($string);
+		if (!\OC::$CLI) {
+			\header($string);
+		}
 	}
 }