diff --git a/src/wp-admin/includes/schema.php b/src/wp-admin/includes/schema.php
index 554adb8136..0dc3df913b 100644
--- a/src/wp-admin/includes/schema.php
+++ b/src/wp-admin/includes/schema.php
@@ -897,13 +897,18 @@ function populate_network( $network_id = 1, $domain = '', $email = '', $site_nam
 	if ( $network_id == $wpdb->get_var( $wpdb->prepare( "SELECT id FROM $wpdb->site WHERE id = %d", $network_id ) ) )
 		$errors->add( 'siteid_exists', __( 'The network already exists.' ) );
 
-	$site_user = get_user_by( 'email', $email );
 	if ( ! is_email( $email ) )
 		$errors->add( 'invalid_email', __( 'You must provide a valid email address.' ) );
 
 	if ( $errors->get_error_code() )
 		return $errors;
 
+	// If a user with the provided email does not exist, default to the current user as the new network admin.
+	$site_user = get_user_by( 'email', $email );
+	if ( false === $site_user ) {
+		$site_user = wp_get_current_user();
+	}
+
 	// Set up site tables.
 	$template = get_option( 'template' );
 	$stylesheet = get_option( 'stylesheet' );
@@ -967,7 +972,7 @@ We hope you enjoy your new site. Thanks!
 
 	$sitemeta = array(
 		'site_name' => $site_name,
-		'admin_email' => $site_user->user_email,
+		'admin_email' => $email,
 		'admin_user_id' => $site_user->ID,
 		'registration' => 'none',
 		'upload_filetypes' => implode( ' ', $upload_filetypes ),