diff --git a/admin/s3-add-inventory.sh b/admin/s3-add-inventory.sh
new file mode 100644
index 00000000..680ee118
--- /dev/null
+++ b/admin/s3-add-inventory.sh
@@ -0,0 +1,24 @@
+#!/bin/sh
+SOURCE_BUCKET="bucket1"
+DESTINATION_BUCKET="bucket2"
+INVENTORY_ID="inventory1"
+
+aws s3api put-bucket-inventory-configuration \
+--bucket $SOURCE_BUCKET \
+--id $INVENTORY_ID \
+--inventory-configuration \
+'{
+    "Schedule": {
+        "Frequency": "Daily"
+    },
+    "IsEnabled": true,
+    "Destination": {
+        "S3BucketDestination": {
+            "Bucket": "arn:aws:s3:::'$DESTINATION_BUCKET'",
+            "Format": "CSV"
+        }
+    },
+    "OptionalFields": ["Size","LastModifiedDate","ETag"],
+    "IncludedObjectVersions": "Current",
+    "Id": "'$INVENTORY_ID'"
+}'
\ No newline at end of file
diff --git a/admin/storage_existing_files b/admin/storage_existing_files
index a195e347..f1bbd1ff 100755
--- a/admin/storage_existing_files
+++ b/admin/storage_existing_files
@@ -37,7 +37,7 @@ foreach ($shardIDs as $shardID) {
 	
 	$sql = "SELECT DISTINCT storageFileID FROM storageFileItems";
 	$ids = Zotero_DB::columnQuery($sql, false, $shardID);
-	
+	if (!$ids) continue;
 	$inserted = 0;
 	$origInsertSQL = "INSERT IGNORE INTO storageFilesExisting VALUES ";
 	
diff --git a/admin/storage_purge b/admin/storage_purge
index 9f36f996..0257adc9 100755
--- a/admin/storage_purge
+++ b/admin/storage_purge
@@ -14,7 +14,8 @@ define('SET_NAME_DIFF', 'storage:keys:diff');
 define('MAX_TIME', time() - (60 * 60 * 24 * 30 * 6)); // 6 months
 define('DRY_RUN', false);
 
-$startKey = empty($argv[1]) ? false : $argv[1];
+// Gzipped CSV file
+$csvFilename = empty($argv[1]) ? false : $argv[1];
 
 $redis = Z_Redis::get();
 
@@ -26,17 +27,7 @@ if (!$redis->srandmember(SET_NAME_EXISTING)) {
 $redis->del(SET_NAME_S3);
 $redis->del(SET_NAME_DIFF);
 
-echo "Listing objects on S3\n";
-
-// Get iterator for all files in S3
-$s3 = Z_Core::$AWS->get('s3');
-$options = [
-	'Bucket' => Z_CONFIG::$S3_BUCKET
-];
-if ($startKey) {
-	$options['Marker'] = $startKey;
-}
-$iterator = $s3->getIterator('ListObjects', $options);
+$input = gzopen($csvFilename, 'r');
 
 $deleted = 0;
 $ignoredS3 = 0;
@@ -44,10 +35,10 @@ $ignoredDB = 0;
 $i = 0;
 $arr = [SET_NAME_S3];
 
-foreach ($iterator as $object) {
-	$key = $object['Key'];
-	$lastModified = $object['LastModified'];
-	
+while (($row = fgetcsv($input)) !== false) {
+	$key = $row[1];
+	$lastModified = $row[2];
+
 	$date = DateTime::createFromFormat('Y-m-d\TH:i:s.uP', $lastModified);
 	if (!$date) {
 		die("Invalid date '$lastModified'\n");
@@ -84,7 +75,7 @@ if (sizeOf($arr) > 1) {
 }
 
 function deleteFromS3() {
-	$s3 = Z_Core::$AWS->get('s3');
+	$s3 = Z_Core::$AWS->createS3();
 	$redis = Z_Redis::get();
 	
 	$deleted = 0;
@@ -102,14 +93,10 @@ function deleteFromS3() {
 		// See if file was marked as used recently in the database. The modification time in S3
 		// isn't updated when an existing file is reused, so this is common.
 		$info = new Zotero_StorageFileInfo;
-		try {
-			$info->parseFromS3Key($key);
-		}
-		// Ignore other files ('bookmarklet_upload.html')
-		catch (Exception $e) {
-			continue;
-		}
 		
+		$info->filename = $key;
+		//$info->zip = ?;
+        
 		$info = Zotero_Storage::getLocalFileInfo($info);
 		if ($info) {
 			$lastAdded = DateTime::createFromFormat('Y-m-d H:i:s', $info['lastAdded']);