diff --git a/editor/editors.go b/editor/editors.go
index 64c0e85..f7b3536 100644
--- a/editor/editors.go
+++ b/editor/editors.go
@@ -106,7 +106,7 @@ func AutocompleteHandler(w http.ResponseWriter, r *http.Request) {
 
 	if err := json.NewDecoder(r.Body).Decode(&args); err != nil {
 		logger.Error(err)
-		http.Error(w, err.Error(), 500)
+		http.Error(w, err.Error(), http.StatusInternalServerError)
 
 		return
 	}
@@ -125,7 +125,7 @@ func AutocompleteHandler(w http.ResponseWriter, r *http.Request) {
 
 	if nil != err {
 		logger.Error(err)
-		http.Error(w, err.Error(), 500)
+		http.Error(w, err.Error(), http.StatusInternalServerError)
 
 		return
 	}
@@ -135,7 +135,7 @@ func AutocompleteHandler(w http.ResponseWriter, r *http.Request) {
 
 	if err := fout.Close(); nil != err {
 		logger.Error(err)
-		http.Error(w, err.Error(), 500)
+		http.Error(w, err.Error(), http.StatusInternalServerError)
 
 		return
 	}
@@ -168,7 +168,7 @@ func AutocompleteHandler(w http.ResponseWriter, r *http.Request) {
 	output, err := cmd.CombinedOutput()
 	if nil != err {
 		logger.Error(err)
-		http.Error(w, err.Error(), 500)
+		http.Error(w, err.Error(), http.StatusInternalServerError)
 
 		return
 	}
@@ -188,7 +188,7 @@ func GetExprInfoHandler(w http.ResponseWriter, r *http.Request) {
 	var args map[string]interface{}
 	if err := json.NewDecoder(r.Body).Decode(&args); err != nil {
 		logger.Error(err)
-		http.Error(w, err.Error(), 500)
+		http.Error(w, err.Error(), http.StatusInternalServerError)
 
 		return
 	}
@@ -233,7 +233,7 @@ func GetExprInfoHandler(w http.ResponseWriter, r *http.Request) {
 	output, err := cmd.CombinedOutput()
 	if nil != err {
 		logger.Error(err)
-		http.Error(w, err.Error(), 500)
+		http.Error(w, err.Error(), http.StatusInternalServerError)
 
 		return
 	}
@@ -264,7 +264,7 @@ func FindDeclarationHandler(w http.ResponseWriter, r *http.Request) {
 	var args map[string]interface{}
 	if err := json.NewDecoder(r.Body).Decode(&args); err != nil {
 		logger.Error(err)
-		http.Error(w, err.Error(), 500)
+		http.Error(w, err.Error(), http.StatusInternalServerError)
 
 		return
 	}
@@ -309,7 +309,7 @@ func FindDeclarationHandler(w http.ResponseWriter, r *http.Request) {
 	output, err := cmd.CombinedOutput()
 	if nil != err {
 		logger.Error(err)
-		http.Error(w, err.Error(), 500)
+		http.Error(w, err.Error(), http.StatusInternalServerError)
 
 		return
 	}
@@ -353,7 +353,7 @@ func FindUsagesHandler(w http.ResponseWriter, r *http.Request) {
 
 	if err := json.NewDecoder(r.Body).Decode(&args); err != nil {
 		logger.Error(err)
-		http.Error(w, err.Error(), 500)
+		http.Error(w, err.Error(), http.StatusInternalServerError)
 
 		return
 	}
@@ -397,7 +397,7 @@ func FindUsagesHandler(w http.ResponseWriter, r *http.Request) {
 	output, err := cmd.CombinedOutput()
 	if nil != err {
 		logger.Error(err)
-		http.Error(w, err.Error(), 500)
+		http.Error(w, err.Error(), http.StatusInternalServerError)
 
 		return
 	}
diff --git a/main.go b/main.go
index 386fbba..5b10d1a 100644
--- a/main.go
+++ b/main.go
@@ -150,6 +150,7 @@ func main() {
 	http.HandleFunc("/notification/ws", handlerWrapper(notification.WSHandler))
 
 	// user
+	http.HandleFunc("/login", handlerWrapper(session.LoginHandler))
 	http.HandleFunc("/logout", handlerWrapper(session.LogoutHandler))
 	http.HandleFunc("/preference", handlerWrapper(session.PreferenceHandler))
 
@@ -219,7 +220,7 @@ func indexHandler(w http.ResponseWriter, r *http.Request) {
 	t, err := template.ParseFiles("views/index.html")
 	if nil != err {
 		logger.Error(err)
-		http.Error(w, err.Error(), 500)
+		http.Error(w, err.Error(), http.StatusInternalServerError)
 
 		return
 	}
@@ -279,7 +280,7 @@ func startHandler(w http.ResponseWriter, r *http.Request) {
 
 	if nil != err {
 		logger.Error(err)
-		http.Error(w, err.Error(), 500)
+		http.Error(w, err.Error(), http.StatusInternalServerError)
 
 		return
 	}
@@ -308,7 +309,7 @@ func keyboardShortcutsHandler(w http.ResponseWriter, r *http.Request) {
 
 	if nil != err {
 		logger.Error(err)
-		http.Error(w, err.Error(), 500)
+		http.Error(w, err.Error(), http.StatusInternalServerError)
 
 		return
 	}
@@ -338,7 +339,7 @@ func aboutHandler(w http.ResponseWriter, r *http.Request) {
 
 	if nil != err {
 		logger.Error(err)
-		http.Error(w, err.Error(), 500)
+		http.Error(w, err.Error(), http.StatusInternalServerError)
 
 		return
 	}
diff --git a/playground/autocomplete.go b/playground/autocomplete.go
index 81d5af0..3894027 100644
--- a/playground/autocomplete.go
+++ b/playground/autocomplete.go
@@ -32,7 +32,7 @@ func AutocompleteHandler(w http.ResponseWriter, r *http.Request) {
 
 	if err := json.NewDecoder(r.Body).Decode(&args); err != nil {
 		logger.Error(err)
-		http.Error(w, err.Error(), 500)
+		http.Error(w, err.Error(), http.StatusInternalServerError)
 
 		return
 	}
@@ -61,7 +61,7 @@ func AutocompleteHandler(w http.ResponseWriter, r *http.Request) {
 	output, err := cmd.CombinedOutput()
 	if nil != err {
 		logger.Error(err)
-		http.Error(w, err.Error(), 500)
+		http.Error(w, err.Error(), http.StatusInternalServerError)
 
 		return
 	}
diff --git a/playground/playgrounds.go b/playground/playgrounds.go
index 8191bdf..68c643c 100644
--- a/playground/playgrounds.go
+++ b/playground/playgrounds.go
@@ -97,7 +97,7 @@ func IndexHandler(w http.ResponseWriter, r *http.Request) {
 
 	if nil != err {
 		logger.Error(err)
-		http.Error(w, err.Error(), 500)
+		http.Error(w, err.Error(), http.StatusInternalServerError)
 
 		return
 	}
diff --git a/session/oauthctl.go b/session/oauthctl.go
index 9e4bad3..d13a586 100644
--- a/session/oauthctl.go
+++ b/session/oauthctl.go
@@ -16,6 +16,8 @@ package session
 
 import (
 	"crypto/tls"
+	"github.com/b3log/wide/i18n"
+	"html/template"
 	"math/rand"
 	"net/http"
 	"os"
@@ -141,6 +143,22 @@ func GitHubUserInfo(accessToken string) (ret map[string]interface{}) {
 	return result["data"].(map[string]interface{})
 }
 
+// LoginHandler handles request of show login page.
+func LoginHandler(w http.ResponseWriter, r *http.Request) {
+	model := map[string]interface{}{"conf": conf.Wide, "i18n": i18n.GetAll(conf.Wide.Locale),
+		"locale": conf.Wide.Locale, "ver": conf.WideVersion, "year": time.Now().Year()}
+
+	t, err := template.ParseFiles("views/login.html")
+	if nil != err {
+		logger.Error(err)
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+
+		return
+	}
+
+	t.Execute(w, model)
+}
+
 // LogoutHandler handles request of user logout (exit).
 func LogoutHandler(w http.ResponseWriter, r *http.Request) {
 	result := util.NewResult()
diff --git a/session/users.go b/session/users.go
index 5522a0f..002b2d8 100644
--- a/session/users.go
+++ b/session/users.go
@@ -74,7 +74,7 @@ func PreferenceHandler(w http.ResponseWriter, r *http.Request) {
 
 		if nil != err {
 			logger.Error(err)
-			http.Error(w, err.Error(), 500)
+			http.Error(w, err.Error(), http.StatusInternalServerError)
 
 			user.GoBuildArgsForLinux = tmpLinux
 			user.GoBuildArgsForWindows = tmpWindows
diff --git a/static/js/playground.js b/static/js/playground.js
index ae6a253..b296cea 100644
--- a/static/js/playground.js
+++ b/static/js/playground.js
@@ -218,7 +218,7 @@ var playground = {
                 if (!hovered) {
                     $(".menu .share-panel").hide();
                 }
-            }, 500);
+            }, http.StatusInternalServerError;
         });
 
         $(".menu .share-panel").hover(function () {