diff --git a/wp-activate.php b/wp-activate.php
index 0607dae840..6aae1ca8a0 100644
--- a/wp-activate.php
+++ b/wp-activate.php
@@ -18,6 +18,8 @@ if ( !is_multisite() ) {
 	die();
 }
 
+nocache_headers();
+
 if ( is_object( $wp_object_cache ) )
 	$wp_object_cache->cache_enabled = false;
 
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 1460917df1..18db84bf7d 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.9.6-alpha-43064';
+$wp_version = '4.9.6-alpha-43066';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.