diff --git a/wp-admin/includes/class-wp-upgrader.php b/wp-admin/includes/class-wp-upgrader.php
--- a/wp-admin/includes/class-wp-upgrader.php
+++ b/wp-admin/includes/class-wp-upgrader.php
@@ -816,11 +816,11 @@
 			$this->skin->feedback('maintenance_start');
 			// Create maintenance file to signal that we are upgrading
 			$maintenance_string = '<?php $upgrading = ' . time() . '; ?>';
-			$wp_filesystem->delete($file);
+			$wp_filesystem->delete($file, false, 'f');
 			$wp_filesystem->put_contents($file, $maintenance_string, FS_CHMOD_FILE);
-		} elseif ( ! $enable && $wp_filesystem->exists( $file ) ) {
+		} else {
 			$this->skin->feedback('maintenance_end');
-			$wp_filesystem->delete($file);
+			$wp_filesystem->delete($file, false, 'f');
 		}
 	}