diff --git a/hgdriver/hgdev/hg_scanner_239.cpp b/hgdriver/hgdev/hg_scanner_239.cpp
index af480c5..d2ff71e 100644
--- a/hgdriver/hgdev/hg_scanner_239.cpp
+++ b/hgdriver/hgdev/hg_scanner_239.cpp
@@ -1385,7 +1385,9 @@ std::string hg_scanner_239::get_serial_num(void)
 }
 std::string hg_scanner_239::get_ip(void)
 {
-	return control_fetch(setting3399::SR_GET_IPADDR, 0, 40);
+	int len = 0;
+	read_register(setting3399::SR_GET_SERIAL_LEN, &len);
+	return control_fetch(setting3399::SR_GET_IPADDR, 0, len);
 }
 std::string hg_scanner_239::get_device_model(void)
 {
diff --git a/hgdriver/hgdev/scanner_manager.cpp b/hgdriver/hgdev/scanner_manager.cpp
index 31e2f47..18f7b43 100644
--- a/hgdriver/hgdev/scanner_manager.cpp
+++ b/hgdriver/hgdev/scanner_manager.cpp
@@ -535,7 +535,7 @@ scanner_err hg_scanner_mgr::get_about_info(scanner_handle h, void* data, unsigne
         set_appendix_info_for_about(about, ptr, count, GET_LANG(BRAND_TITLE_FIRM_VERSION,&islang), scanner->get_firmware_version().c_str(), NULL);
         set_appendix_info_for_about(about, ptr, count, GET_LANG(BRAND_TITLE_SERIAL_NUM,&islang), scanner->get_serial_num().c_str(), NULL);
         info = scanner->get_ip();
-        if (info.length() > 10)
+        if (info.length() > 10 && !info.empty())
             set_appendix_info_for_about(about, ptr, count, GET_LANG(BRAND_TITLE_IP,&islang), info.c_str(), NULL);
         info.clear();
         info = scanner->get_device_model();