diff --git a/dao/role.go b/dao/role.go
index 43062a1..8bd9b9e 100644
--- a/dao/role.go
+++ b/dao/role.go
@@ -58,6 +58,10 @@ func IsAdminRole(userIDOrUsername interface{}) (bool, error) {
 		return false, fmt.Errorf("invalid parameter, only int and string are supported: %v", userIDOrUsername)
 	}
 
+	if len(u.Username) == 0 {
+		return false, nil
+	}
+
 	user, err := GetUser(u)
 	if err != nil {
 		return false, err
diff --git a/utils/registry/auth/handler.go b/utils/registry/auth/handler.go
index de1e22b..4d1e609 100644
--- a/utils/registry/auth/handler.go
+++ b/utils/registry/auth/handler.go
@@ -19,12 +19,14 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"io/ioutil"
 	"net/http"
 	"net/url"
 	"strings"
 
 	token_util "github.com/vmware/harbor/service/token"
 	"github.com/vmware/harbor/utils/log"
+	"github.com/vmware/harbor/utils/registry/errors"
 )
 
 // Handler authorizes the request when encounters a 401 error
@@ -109,12 +111,19 @@ func (t *standardTokenHandler) AuthorizeRequest(req *http.Request, params map[st
 		return err
 	}
 
-	if resp.StatusCode != http.StatusOK {
-		return fmt.Errorf("error occured when get token from %s, status code: %d, status info: %s",
-			realm, resp.StatusCode, resp.Status)
+	defer resp.Body.Close()
+
+	b, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return err
 	}
 
-	defer resp.Body.Close()
+	if resp.StatusCode != http.StatusOK {
+		return error.Error{
+			StatusCode: resp.StatusCode,
+			Message:    string(b),
+		}
+	}
 
 	decoder := json.NewDecoder(resp.Body)
 
diff --git a/utils/registry/error.go b/utils/registry/error.go
deleted file mode 100644
index dda4e44..0000000
--- a/utils/registry/error.go
+++ /dev/null
@@ -1,38 +0,0 @@
-/*
-   Copyright (c) 2016 VMware, Inc. All Rights Reserved.
-   Licensed under the Apache License, Version 2.0 (the "License");
-   you may not use this file except in compliance with the License.
-   You may obtain a copy of the License at
-
-       http://www.apache.org/licenses/LICENSE-2.0
-
-   Unless required by applicable law or agreed to in writing, software
-   distributed under the License is distributed on an "AS IS" BASIS,
-   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-   See the License for the specific language governing permissions and
-   limitations under the License.
-*/
-
-package registry
-
-import (
-	"fmt"
-)
-
-// Error : if response's status code is not 200 or does not meet requirement,
-// an Error instance will be returned
-type Error struct {
-	StatusCode int
-	Message    string
-}
-
-// Error ...
-func (e Error) Error() string {
-	return fmt.Sprintf("%d %s", e.StatusCode, e.Message)
-}
-
-// ParseError parses err, if err is type Error, convert it to Error
-func ParseError(err error) (Error, bool) {
-	e, ok := err.(Error)
-	return e, ok
-}