diff --git a/src/common/notifier/scan_policy_notitification_handler.go b/src/common/notifier/scan_policy_notitification_handler.go
index e3f7d3530..2949b3fb5 100644
--- a/src/common/notifier/scan_policy_notitification_handler.go
+++ b/src/common/notifier/scan_policy_notitification_handler.go
@@ -100,7 +100,9 @@ func schedulePolicy(notification ScanPolicyNotification) error {
 		OffsetTime: notification.DailyTime,
 	})
 	attachTask := task.NewScanAllTask()
-	schedulePolicy.AttachTasks(attachTask)
+	if err := schedulePolicy.AttachTasks(attachTask); err != nil {
+		return err
+	}
 
 	return scheduler.DefaultScheduler.Schedule(schedulePolicy)
 }
diff --git a/src/common/utils/utils.go b/src/common/utils/utils.go
index 0cc64b402..69f01001c 100644
--- a/src/common/utils/utils.go
+++ b/src/common/utils/utils.go
@@ -100,7 +100,9 @@ func TestTCPConn(addr string, timeout, interval int) error {
 					time.Sleep(time.Duration(interval) * time.Second)
 					continue
 				}
-				conn.Close()
+				if err = conn.Close(); err != nil {
+					log.Errorf("failed to close the connection: %v", err)
+				}
 				success <- 1
 				break
 			}
diff --git a/src/jobservice/job/logger.go b/src/jobservice/job/logger.go
index b09f5d6f5..59a1a2a3b 100644
--- a/src/jobservice/job/logger.go
+++ b/src/jobservice/job/logger.go
@@ -28,7 +28,7 @@ func NewLogger(j Job) (*log.Logger, error) {
 	logFile := j.LogPath()
 	d := filepath.Dir(logFile)
 	if _, err := os.Stat(d); os.IsNotExist(err) {
-		err := os.MkdirAll(d, 0755)
+		err := os.MkdirAll(d, 0700)
 		if err != nil {
 			log.Errorf("Failed to create directory for log file %s, the error: %v", logFile, err)
 		}
diff --git a/src/ui/auth/ldap/ldap.go b/src/ui/auth/ldap/ldap.go
index e4dd938bd..7c4034946 100644
--- a/src/ui/auth/ldap/ldap.go
+++ b/src/ui/auth/ldap/ldap.go
@@ -158,9 +158,11 @@ func (l *Auth) PostAuthenticate(u *models.User) error {
 			if !Re.MatchString(u.Email) {
 				log.Debugf("Not a valid email address: %v, skip to sync", u.Email)
 			} else {
-				dao.ChangeUserProfile(*u, "Email")
+				if err = dao.ChangeUserProfile(*u, "Email"); err != nil {
+					u.Email = dbUser.Email
+					log.Errorf("failed to sync user email: %v", err)
+				}
 			}
-			u.Email = dbUser.Email
 		}
 
 		return nil
diff --git a/src/ui/main.go b/src/ui/main.go
index f322db446..4a8d8bf2a 100644
--- a/src/ui/main.go
+++ b/src/ui/main.go
@@ -116,7 +116,9 @@ func main() {
 	scheduler.DefaultScheduler.Start()
 
 	//Subscribe the policy change topic.
-	notifier.Subscribe(notifier.ScanAllPolicyTopic, &notifier.ScanPolicyNotificationHandler{})
+	if err = notifier.Subscribe(notifier.ScanAllPolicyTopic, &notifier.ScanPolicyNotificationHandler{}); err != nil {
+		log.Errorf("failed to subscribe scan all policy change topic: %v", err)
+	}
 
 	//Get policy configuration.
 	scanAllPolicy := config.ScanAllPolicy()
@@ -129,7 +131,10 @@ func main() {
 		}
 
 		//Send notification to handle first policy change.
-		notifier.Publish(notifier.ScanAllPolicyTopic, notifier.ScanPolicyNotification{Type: scanAllPolicy.Type, DailyTime: (int64)(dailyTime)})
+		if err = notifier.Publish(notifier.ScanAllPolicyTopic,
+			notifier.ScanPolicyNotification{Type: scanAllPolicy.Type, DailyTime: (int64)(dailyTime)}); err != nil {
+			log.Errorf("failed to publish scan all policy topic: %v", err)
+		}
 	}
 
 	if err := core.Init(); err != nil {