diff --git a/lib/services/service.py b/lib/services/service.py
index faf1d36..af8e076 100644
--- a/lib/services/service.py
+++ b/lib/services/service.py
@@ -123,6 +123,8 @@ class Service(object):
         pass
 
     def pre_execute(self, host):
+        self.errorcode = 0
+        self.errormessage = None
         pass
 
     def parse_result(self, executionResult):