diff --git a/uc_auction.module b/uc_auction.module
index eeefccf..083390f 100644
--- a/uc_auction.module
+++ b/uc_auction.module
@@ -716,8 +716,8 @@ function uc_auction_cron() {
     if (variable_get('uc_auction_notify_win', TRUE)) {
       // …we need to do some loading.
       $node = node_load($nid->nid);
-      $high_user = user_load($node->uc_auction['high_bid_uid']);
-      if ($high_user->uid) {
+      $high_user = $node->uc_auction['high_bid_uid'] ? user_load($node->uc_auction['high_bid_uid']) : FALSE;
+      if ($high_user) {
         drupal_mail('uc_auction', 'uc_auction_notify_win', $high_user->mail, user_preferred_language($high_user), array('node' => $node, 'user' => $high_user));
         watchdog('uc auction', 'Auction won notification for !item sent to @user.', array('@user' => $high_user->name, '!item' => l($node->title, "node/{$node->nid}")));
       }