diff --git a/webdav.php b/webdav.php
index 05aed7a4f3..76d3062767 100644
--- a/webdav.php
+++ b/webdav.php
@@ -89,6 +89,9 @@ catch (egw_exception_no_permission_app $e)
 }
 $headertime = microtime(true);
 
+// switch of output buffering (switched on in header), as otherwise we run against memory_limit, for big files
+ob_end_flush();
+
 $webdav_server = new vfs_webdav_server();
 $webdav_server->ServeRequest();
 //error_log(sprintf("WebDAV %s request took %5.3f s (header include took %5.3f s)",$_SERVER['REQUEST_METHOD'],microtime(true)-$starttime,$headertime-$starttime));