diff --git a/lib/files.php b/lib/files.php
index 57ebb9005a..f1cf7573ba 100644
--- a/lib/files.php
+++ b/lib/files.php
@@ -64,7 +64,7 @@ class OC_Files {
 			set_time_limit(0);
 			$zip = new ZipArchive();
 			$filename = get_temp_dir()."/ownCloud.zip";
-			if ($zip->open($filename, ZIPARCHIVE::CREATE)!==TRUE) {
+			if ($zip->open($filename, ZIPARCHIVE::CREATE | ZIPARCHIVE::OVERWRITE)!==TRUE) {
 				exit("cannot open <$filename>\n");
 			}
 			foreach($files as $file){
@@ -85,7 +85,7 @@ class OC_Files {
 			set_time_limit(0);
 			$zip = new ZipArchive();
 			$filename = get_temp_dir()."/ownCloud.zip";
-			if ($zip->open($filename, ZIPARCHIVE::CREATE)!==TRUE) {
+			if ($zip->open($filename, ZIPARCHIVE::CREATE | ZIPARCHIVE::OVERWRITE)!==TRUE) {
 				exit("cannot open <$filename>\n");
 			}
 			$file=$dir.'/'.$files;