diff --git a/server/web3bcspider/services/erc721_refresher.js b/server/web3bcspider/services/erc721_refresher.js
index a73e260..1951956 100644
--- a/server/web3bcspider/services/erc721_refresher.js
+++ b/server/web3bcspider/services/erc721_refresher.js
@@ -41,7 +41,7 @@ class Erc721Refresher extends BaseService {
           this.getContractAddress()
         ]);
       if (err) {
-        throw err;
+        throw new Error(err);
       }
       if (rows.length > 0) {
         this.progInfo['pendingCount'] = rows.length;