diff --git a/src/web/admin/admin_expiration_list.html b/src/web/admin/admin_expiration_list.html
index e35a4d6..6973e8f 100644
--- a/src/web/admin/admin_expiration_list.html
+++ b/src/web/admin/admin_expiration_list.html
@@ -1,10 +1,14 @@
-﻿<html>
-
+﻿<!DOCTYPE html>
+<html>
 
 <head>
+	<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
+	<meta charset="UTF-8">
 	<title>마우스 타자 관리자 페이지</title>
+
 	<link rel="icon" href="/favicon.ico" type="image/x-icon" />
 	<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
+
 	<link href="../../../resources/bootstrap/css/bootstrap.min.css" rel="stylesheet">
 
 	<script type="text/javascript" src="./../../../resources/jquery/jquery-3.3.1.min.js"></script>
diff --git a/src/web/admin/admin_header.html b/src/web/admin/admin_header.html
index 4f5fdcb..2b41528 100644
--- a/src/web/admin/admin_header.html
+++ b/src/web/admin/admin_header.html
@@ -1,4 +1,6 @@
-﻿<style>
+﻿<!DOCTYPE html>
+
+<style>
 
 .home {
 	display: inline-block;
@@ -26,7 +28,10 @@
 	<div class="container">
 
 		<div class="navbar-header">
-			<a class="navbar-brand" href="javascript:void(0);" onClick="goHome()" href="">[ chocomae.com ]</a>
+			<a class="btn btn-warning btn-lg vertical-align: middle; align-items-center" href="./../main/index.html">
+				<img src="./../../../resources/image/icon/icon_chocomae.png" style="position: relative; bottom: 2px; width: 24px; height: auto;">
+				&nbsp;초코마에
+			</a>
 		</div>
 
 		<div class="eyebrow ml-auto mt-0 d-md-flex align-items-center">
diff --git a/src/web/admin/admin_register_list.html b/src/web/admin/admin_register_list.html
index 80542ef..5aa17fc 100644
--- a/src/web/admin/admin_register_list.html
+++ b/src/web/admin/admin_register_list.html
@@ -1,9 +1,14 @@
-﻿<html>
+﻿<!DOCTYPE html>
+<html>
 
 <head>
+	<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
+	<meta charset="UTF-8">
 	<title>마우스 타자 관리자 페이지</title>
+
 	<link rel="icon" href="/favicon.ico" type="image/x-icon" />
 	<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
+
 	<link href="../../../resources/bootstrap/css/bootstrap.min.css" rel="stylesheet">
 
 	<script type="text/javascript" src="./../../../resources/jquery/jquery-3.3.1.min.js"></script>
diff --git a/src/web/admin/admin_send_email.html b/src/web/admin/admin_send_email.html
index 374b892..74f0d38 100644
--- a/src/web/admin/admin_send_email.html
+++ b/src/web/admin/admin_send_email.html
@@ -1,10 +1,14 @@
-﻿<html>
-
+﻿<!DOCTYPE html>
+<html>
 
 <head>
+	<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
+	<meta charset="UTF-8">
 	<title>마우스 타자 관리자 페이지</title>
+
 	<link rel="icon" href="/favicon.ico" type="image/x-icon" />
 	<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
+
 	<link href="../../../resources/bootstrap/css/bootstrap.min.css" rel="stylesheet">
 
 	<script type="text/javascript" src="./../../../resources/jquery/jquery-3.3.1.min.js"></script>
diff --git a/src/web/admin/admin_upgrade_list.html b/src/web/admin/admin_upgrade_list.html
index 01472c3..44c47f4 100644
--- a/src/web/admin/admin_upgrade_list.html
+++ b/src/web/admin/admin_upgrade_list.html
@@ -1,10 +1,14 @@
-﻿<html>
-
+﻿<!DOCTYPE html>
+<html>
 
 <head>
+	<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
+	<meta charset="UTF-8">
 	<title>마우스 타자 관리자 페이지</title>
+
 	<link rel="icon" href="/favicon.ico" type="image/x-icon" />
 	<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
+
 	<link href="../../../resources/bootstrap/css/bootstrap.min.css" rel="stylesheet">
 
 	<script type="text/javascript" src="./../../../resources/jquery/jquery-3.3.1.min.js"></script>
diff --git a/src/web/admin/login.html b/src/web/admin/login.html
index e6e179f..e98ef1b 100644
--- a/src/web/admin/login.html
+++ b/src/web/admin/login.html
@@ -1,10 +1,14 @@
-﻿<html>
+﻿<!DOCTYPE html>
+<html>
 
 <head>
+	<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
+	<meta charset="UTF-8">
 	<title>관리자 페이지</title>
-	<link rel="icon" href="/favicon.ico" type="image/x-icon" />
+
 	<link rel="icon" href="/favicon.ico" type="image/x-icon" />
 	<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
+
 	<link href="../../../resources/bootstrap/css/bootstrap.min.css" rel="stylesheet">
 
 	<script type="text/javascript" src="./../../../resources/jquery/jquery-3.3.1.min.js"></script>
diff --git a/src/web/client/card_matching.html b/src/web/client/card_matching.html
index 6b39e6a..504b6a1 100644
--- a/src/web/client/card_matching.html
+++ b/src/web/client/card_matching.html
@@ -1,10 +1,13 @@
 <!DOCTYPE html>
 <html>
 	<head>
+		<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 		<meta charset="UTF-8">
 		<title>카드 짝 맞추기, 초코마에</title>
 		<meta name="description" CONTENT="카드 짝 맞추기 Matching card pair, 마우스 더블 클릭 연습 앱 mouse double click practice app, 초코마에 chcomae">
 
+		<link rel="icon" href="/favicon.ico" type="image/x-icon" />
+		<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
 
 		<!-- <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> -->
 		<!-- <script src="https://cdnjs.cloudflare.com/ajax/libs/phaser/2.6.2/phaser.js"></script> -->
diff --git a/src/web/client/grilled_meat.html b/src/web/client/grilled_meat.html
index 786adbf..ec650aa 100644
--- a/src/web/client/grilled_meat.html
+++ b/src/web/client/grilled_meat.html
@@ -1,10 +1,13 @@
 <!DOCTYPE html>
 <html>
 	<head>
+		<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 		<meta charset="UTF-8">
 		<title>고기 굽기, 초코마에</title>
 		<meta name="description" CONTENT="고기 굽기 Grilling meat, 마우스 드래그 연습 앱 mouse drag practice app, 초코마에 chcomae">
 
+		<link rel="icon" href="/favicon.ico" type="image/x-icon" />
+		<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
 
 		<!-- <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> -->
 		<!-- <script src="https://cdnjs.cloudflare.com/ajax/libs/phaser/2.6.2/phaser.js"></script> -->
diff --git a/src/web/client/login.html b/src/web/client/login.html
index 8128a6a..35b46f7 100644
--- a/src/web/client/login.html
+++ b/src/web/client/login.html
@@ -1,9 +1,12 @@
 <!DOCTYPE html>
 <html>
 	<head>
+		<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 		<meta charset="UTF-8">
 		<title>로그인</title>
 
+		<link rel="icon" href="/favicon.ico" type="image/x-icon" />
+		<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
 
 		<!-- <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> -->
 		<!-- <script src="https://cdnjs.cloudflare.com/ajax/libs/phaser/2.6.2/phaser.js"></script> -->
diff --git a/src/web/client/menu_app.html b/src/web/client/menu_app.html
index 22f0ddd..885c877 100644
--- a/src/web/client/menu_app.html
+++ b/src/web/client/menu_app.html
@@ -1,9 +1,12 @@
 <!DOCTYPE html>
 <html>
 	<head>
+		<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 		<meta charset="UTF-8">
 		<title>메뉴</title>
 
+		<link rel="icon" href="/favicon.ico" type="image/x-icon" />
+		<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
 
 		<!-- <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> -->
 		<!-- <script src="https://cdnjs.cloudflare.com/ajax/libs/phaser/2.6.2/phaser.js"></script> -->
diff --git a/src/web/client/menu_app_play_free.html b/src/web/client/menu_app_play_free.html
index bd72bd1..c362802 100644
--- a/src/web/client/menu_app_play_free.html
+++ b/src/web/client/menu_app_play_free.html
@@ -1,9 +1,12 @@
 <!DOCTYPE html>
 <html>
 	<head>
+		<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 		<meta charset="UTF-8">
 		<title>무료 플레이어 메뉴, 초코마에</title>
 
+		<link rel="icon" href="/favicon.ico" type="image/x-icon" />
+		<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
 
 		<!-- <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> -->
 		<!-- <script src="https://cdnjs.cloudflare.com/ajax/libs/phaser/2.6.2/phaser.js"></script> -->
diff --git a/src/web/client/menu_app_test_player.html b/src/web/client/menu_app_test_player.html
index a7c9472..d86220b 100644
--- a/src/web/client/menu_app_test_player.html
+++ b/src/web/client/menu_app_test_player.html
@@ -1,9 +1,13 @@
 <!DOCTYPE html>
 <html>
 	<head>
+		<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 		<meta charset="UTF-8">
 		<title>테스트 플레이어 메뉴, 초코마에</title>
 
+		<link rel="icon" href="/favicon.ico" type="image/x-icon" />
+		<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
+
 		<script type="text/javascript" src="./../../../resources/jquery/jquery-3.3.1.min.js"></script>
 		<script type="text/javascript" src="./../js/main.js"></script>
 		<script type="text/javascript" src="./../js/lib/account_validator.js"></script>
diff --git a/src/web/client/menu_typing_practice.html b/src/web/client/menu_typing_practice.html
index a1a61ed..198583e 100644
--- a/src/web/client/menu_typing_practice.html
+++ b/src/web/client/menu_typing_practice.html
@@ -1,9 +1,12 @@
 <!DOCTYPE html>
 <html>
 	<head>
+		<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 		<meta charset="UTF-8">
 		<title>타자 연습 메뉴</title>
 
+		<link rel="icon" href="/favicon.ico" type="image/x-icon" />
+		<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
 
 		<!-- <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> -->
 		<!-- <script src="https://cdnjs.cloudflare.com/ajax/libs/phaser/2.6.2/phaser.js"></script> -->
diff --git a/src/web/client/menu_typing_test.html b/src/web/client/menu_typing_test.html
index b459da6..14d11b4 100644
--- a/src/web/client/menu_typing_test.html
+++ b/src/web/client/menu_typing_test.html
@@ -1,9 +1,12 @@
 <!DOCTYPE html>
 <html>
 	<head>
+		<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 		<meta charset="UTF-8">
 		<title>타자 시험 메뉴</title>
 
+		<link rel="icon" href="/favicon.ico" type="image/x-icon" />
+		<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
 
 		<!-- <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> -->
 		<!-- <script src="https://cdnjs.cloudflare.com/ajax/libs/phaser/2.6.2/phaser.js"></script> -->
diff --git a/src/web/client/ranking.html b/src/web/client/ranking.html
index cc420e0..a6c0c49 100644
--- a/src/web/client/ranking.html
+++ b/src/web/client/ranking.html
@@ -1,9 +1,12 @@
 <!DOCTYPE html>
 <html>
 	<head>
+		<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 		<meta charset="UTF-8">
 		<title>순위</title>
 
+		<link rel="icon" href="/favicon.ico" type="image/x-icon" />
+		<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
 
 		<!-- <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> -->
 		<!-- <script src="https://cdnjs.cloudflare.com/ajax/libs/phaser/2.6.2/phaser.js"></script> -->
diff --git a/src/web/client/result.html b/src/web/client/result.html
index d5197fa..f5b67ce 100644
--- a/src/web/client/result.html
+++ b/src/web/client/result.html
@@ -1,9 +1,12 @@
 <!DOCTYPE html>
 <html>
 	<head>
+		<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 		<meta charset="UTF-8">
 		<title>결과</title>
 
+		<link rel="icon" href="/favicon.ico" type="image/x-icon" />
+		<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
 
 		<!-- <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> -->
 		<!-- <script src="https://cdnjs.cloudflare.com/ajax/libs/phaser/2.6.2/phaser.js"></script> -->
diff --git a/src/web/client/space_invaders.html b/src/web/client/space_invaders.html
index 05c9a0a..3b24a5c 100644
--- a/src/web/client/space_invaders.html
+++ b/src/web/client/space_invaders.html
@@ -1,10 +1,13 @@
 <!DOCTYPE html>
 <html>
 	<head>
+		<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 		<meta charset="UTF-8">
 		<title>외계인 침공, 초코마에</title>
 		<meta name="description" CONTENT="외계인 침공 Space Invaders, 마우스 클릭 연습 앱 mouse click practice app, 초코마에 chcomae">
 
+		<link rel="icon" href="/favicon.ico" type="image/x-icon" />
+		<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
 
 		<!-- <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> -->
 		<!-- <script src="https://cdnjs.cloudflare.com/ajax/libs/phaser/2.6.2/phaser.js"></script> -->
diff --git a/src/web/client/start.html b/src/web/client/start.html
index 0651246..65601f8 100644
--- a/src/web/client/start.html
+++ b/src/web/client/start.html
@@ -1,9 +1,12 @@
 <!DOCTYPE html>
 <html>
 	<head>
+		<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 		<meta charset="UTF-8">
 		<title>준비</title>
 
+		<link rel="icon" href="/favicon.ico" type="image/x-icon" />
+		<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
 
 		<!-- <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> -->
 		<!-- <script src="https://cdnjs.cloudflare.com/ajax/libs/phaser/2.6.2/phaser.js"></script> -->
diff --git a/src/web/client/typing_practice.html b/src/web/client/typing_practice.html
index b7808bf..4842a7b 100644
--- a/src/web/client/typing_practice.html
+++ b/src/web/client/typing_practice.html
@@ -1,10 +1,13 @@
 <!DOCTYPE html>
 <html>
 	<head>
+		<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 		<meta charset="UTF-8">
 		<title>타자 연습, 초코마에</title>
 		<meta name="description" CONTENT="타자 연습 typing practice, 한글타자 korean typing, 영문타자 영어타자 English typing, 초코마에 chcomae">
 
+		<link rel="icon" href="/favicon.ico" type="image/x-icon" />
+		<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
 
 		<!-- <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> -->
 		<!-- <script src="https://cdnjs.cloudflare.com/ajax/libs/phaser/2.6.2/phaser.js"></script> -->
diff --git a/src/web/client/typing_test.html b/src/web/client/typing_test.html
index 5f63ee3..5d75a4a 100644
--- a/src/web/client/typing_test.html
+++ b/src/web/client/typing_test.html
@@ -1,10 +1,13 @@
 <!DOCTYPE html>
 <html>
 	<head>
+		<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 		<meta charset="UTF-8">
 		<title>타자 시험, 초코마에</title>
 		<meta name="description" CONTENT="타자 시험 typing test, 한글타자 korean typing, 영문타자 영어타자 English typing, 초코마에 chcomae">
 
+		<link rel="icon" href="/favicon.ico" type="image/x-icon" />
+		<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
 
 		<!-- <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> -->
 		<!-- <script src="https://cdnjs.cloudflare.com/ajax/libs/phaser/2.6.2/phaser.js"></script> -->
diff --git a/src/web/client/whac_a_mole.html b/src/web/client/whac_a_mole.html
index 3c0a4cb..278470a 100644
--- a/src/web/client/whac_a_mole.html
+++ b/src/web/client/whac_a_mole.html
@@ -1,10 +1,13 @@
 <!DOCTYPE html>
 <html>
 	<head>
+		<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 		<meta charset="UTF-8">
 		<title>영어 타자 앱-두더지 타자, 초코마에</title>
 		<meta name="description" CONTENT="Whac a Mole 두더지 타자, English typing app 영어 타자 앱, chcomae 초코마에">
 
+		<link rel="icon" href="/favicon.ico" type="image/x-icon" />
+		<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
 
 		<!-- <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js"></script> -->
 		<!-- <script src="https://cdnjs.cloudflare.com/ajax/libs/phaser/2.6.2/phaser.js"></script> -->
diff --git a/src/web/maestro/maestro_test_account_app_menu.html b/src/web/maestro/maestro_test_account_app_menu.html
index 813cde8..c7dc17b 100644
--- a/src/web/maestro/maestro_test_account_app_menu.html
+++ b/src/web/maestro/maestro_test_account_app_menu.html
@@ -2,6 +2,7 @@
 
 
 <head>
+	<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 	<meta charset="UTF-8">
 	<title>마에스트로 체험</title>
 	<meta name="description" CONTENT="테스트 마에스트로 체험 Test maestro experience , 초코마에 chcomae">
@@ -26,9 +27,9 @@
 				"",
 
 				function(jsonData) {
-					let maestroID = jsonData["maestroID"];
-					let playerID = jsonData["playerID"];
-					let playerName = jsonData["playerName"];
+					var maestroID = jsonData["maestroID"];
+					var playerID = jsonData["playerID"];
+					var playerName = jsonData["playerName"];
 
 					console.log("maestroID : " + maestroID);
 					console.log("playerID : " + playerID);
diff --git a/src/web/maestro/main_menu.html b/src/web/maestro/main_menu.html
index a601742..51f2b95 100644
--- a/src/web/maestro/main_menu.html
+++ b/src/web/maestro/main_menu.html
@@ -2,12 +2,14 @@
 
 
 <head>
+	<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 	<meta charset="UTF-8">
 	<title>마에스트로 메뉴, 초코마에</title>
 	<meta name="description" CONTENT="마에스트로 메뉴 Maestro menu , 초코마에 chcomae">
 
 	<link rel="icon" href="/favicon.ico" type="image/x-icon" />
 	<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
+
 	<link href="../../../resources/font/open-iconic-master/font/css/open-iconic-bootstrap.css" rel="stylesheet">
 	<link href="../../../resources/bootstrap/css/bootstrap.min.css" rel="stylesheet">
 
diff --git a/src/web/maestro/setup.html b/src/web/maestro/setup.html
index fd714c2..acf5aa6 100644
--- a/src/web/maestro/setup.html
+++ b/src/web/maestro/setup.html
@@ -2,12 +2,14 @@
 
 
 <head>
+	<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 	<meta charset="UTF-8">
 	<title>마에스트로 정보 변경</title>
 	<meta name="description" CONTENT="마에스트로 정보 변경 Maestro setting change info, 초코마에 chcomae">
 
 	<link rel="icon" href="/favicon.ico" type="image/x-icon" />
 	<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
+
 	<link href="../../../resources/font/open-iconic-master/font/css/open-iconic-bootstrap.css" rel="stylesheet">
 	<link href="../../../resources/bootstrap/css/bootstrap.min.css" rel="stylesheet">
 
diff --git a/src/web/maestro/upgrade.html b/src/web/maestro/upgrade.html
index 1e13587..c6c4653 100644
--- a/src/web/maestro/upgrade.html
+++ b/src/web/maestro/upgrade.html
@@ -2,12 +2,14 @@
 
 
 <head>
+	<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 	<meta charset="UTF-8">
 	<title>마에스트로 업그레이드</title>
 	<meta name="description" CONTENT="마에스트로 업그레이드 신청 Maestro upgrade, 초코마에 chcomae">
 
 	<link rel="icon" href="/favicon.ico" type="image/x-icon" />
 	<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
+
 	<link href="../../../resources/font/open-iconic-master/font/css/open-iconic-bootstrap.css" rel="stylesheet">
 	<link href="../../../resources/bootstrap/css/bootstrap.min.css" rel="stylesheet">
 
diff --git a/src/web/main/faq.html b/src/web/main/faq.html
index 8ec2c59..8547c69 100644
--- a/src/web/main/faq.html
+++ b/src/web/main/faq.html
@@ -2,12 +2,14 @@
 
 
 <head>
+	<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 	<meta charset="UTF-8">
 	<title>FAQ, 초코마에</title>
 	<meta name="description" CONTENT="FAQ 자주 묻는 질문, 초코마에 chcomae">
 
 	<link rel="icon" href="/favicon.ico" type="image/x-icon" />
 	<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
+
 	<link href="../../../resources/font/open-iconic-master/font/css/open-iconic-bootstrap.css" rel="stylesheet">
 	<link href="../../../resources/bootstrap/css/bootstrap.min.css" rel="stylesheet">
 
diff --git a/src/web/main/free_player_app_menu.html b/src/web/main/free_player_app_menu.html
index b4315b5..70f0373 100644
--- a/src/web/main/free_player_app_menu.html
+++ b/src/web/main/free_player_app_menu.html
@@ -2,9 +2,11 @@
 
 
 <head>
+	<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 	<meta charset="UTF-8">
 	<title>초코마에 무료 사용자</title>
 	<meta name="description" CONTENT="무료 사용자 플레이어 Free User Player, 초코마에 chcomae">
+
 	<link rel="icon" href="/favicon.ico" type="image/x-icon" />
 	<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
 
@@ -25,11 +27,11 @@
 				"",
 
 				function(jsonData) {
-					let maestroID = jsonData["maestroID"];
-					let maestroAccountType = jsonData["maestroAccountType"];
-					let playerID = jsonData["playerID"];
-					let playerAccountType = jsonData["playerAccountType"];
-					let playerName = jsonData["playerName"];
+					var maestroID = jsonData["maestroID"];
+					var maestroAccountType = jsonData["maestroAccountType"];
+					var playerID = jsonData["playerID"];
+					var playerAccountType = jsonData["playerAccountType"];
+					var playerName = jsonData["playerName"];
 
 					console.log("maestroID : " + maestroID);
 					console.log("maestroAccountType : " + maestroAccountType);
diff --git a/src/web/main/index.html b/src/web/main/index.html
index a04920d..fa7b715 100644
--- a/src/web/main/index.html
+++ b/src/web/main/index.html
@@ -2,12 +2,14 @@
 
 
 <head>
+	<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 	<meta charset="UTF-8">
 	<title>초코마에</title>
 	<meta name="description" CONTENT="마우스 타자 연습 앱 Mouse tyiping taja practice app, 한글타자 영문타자 Korean typing English typing, 초코마에 chcomae">
 
 	<link rel="icon" href="/favicon.ico" type="image/x-icon" />
 	<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
+
 	<link href="../../../resources/font/open-iconic-master/font/css/open-iconic-bootstrap.css" rel="stylesheet">
 	<link href="../../../resources/bootstrap/css/bootstrap.min.css" rel="stylesheet">
 
diff --git a/src/web/main/login.html b/src/web/main/login.html
index 4abc6fd..e34defd 100644
--- a/src/web/main/login.html
+++ b/src/web/main/login.html
@@ -2,12 +2,14 @@
 
 
 <head>
+	<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 	<meta charset="UTF-8">
 	<title>마에스트로 로그인</title>
 	<meta name="description" CONTENT="마에스트로 로그인 Maestro login, 초코마에 chcomae">
 
 	<link rel="icon" href="/favicon.ico" type="image/x-icon" />
 	<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
+
 	<link href="../../../resources/font/open-iconic-master/font/css/open-iconic-bootstrap.css" rel="stylesheet">
 	<link href="../../../resources/bootstrap/css/bootstrap.min.css" rel="stylesheet">
 
diff --git a/src/web/main/register.html b/src/web/main/register.html
index ff832c9..cbcf900 100644
--- a/src/web/main/register.html
+++ b/src/web/main/register.html
@@ -2,12 +2,14 @@
 
 
 <head>
+	<meta http-equiv="X-UA-Compatible" content="IE=Edge" />
 	<meta charset="UTF-8">
 	<title>마에스트로 계정 등록</title>
 	<meta name="description" CONTENT="마에스트로 계정 유료 등록 Maestro account registration, 초코마에 chcomae">
 
 	<link rel="icon" href="/favicon.ico" type="image/x-icon" />
 	<link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" />
+
 	<link href="../../../resources/font/open-iconic-master/font/css/open-iconic-bootstrap.css" rel="stylesheet">
 	<link href="../../../resources/bootstrap/css/bootstrap.min.css" rel="stylesheet">
 
diff --git a/src/web/module/home_section.html b/src/web/module/home_section.html
index b3a50ce..343bdc6 100644
--- a/src/web/module/home_section.html
+++ b/src/web/module/home_section.html
@@ -6,9 +6,9 @@ function loadMaestroExperienceAccount() {
 		"",
 
 		(function(jsonData) {
-			let maestroID = jsonData["maestroID"];
-			let playerID = jsonData["playerID"];
-			let playerName = jsonData["playerName"];
+			var maestroID = jsonData["maestroID"];
+			var playerID = jsonData["playerID"];
+			var playerName = jsonData["playerName"];
 
 			console.log("maestroID : " + maestroID);
 			console.log("playerID : " + playerID);
@@ -26,7 +26,7 @@ function loadMaestroExperienceAccount() {
 		})
 
 	);
-	let xhr = new XMLHttpRequest(); //new로 생성.
+	var xhr = new XMLHttpRequest(); //new로 생성.
 }
 
 function experienceMaestro() {
diff --git a/src/web/module/maestro_section_add_player.html b/src/web/module/maestro_section_add_player.html
index a23cbe6..1f320d2 100644
--- a/src/web/module/maestro_section_add_player.html
+++ b/src/web/module/maestro_section_add_player.html
@@ -17,8 +17,8 @@ $(document).ready(function() {
 });
 
 function addPlayer() {
-	let playerName = $("#player_name").val();
-	let enterCode = $("#entercode").val();
+	var playerName = $("#player_name").val();
+	var enterCode = $("#entercode").val();
 
 	if(playerName.length === 0) {
 		onErrorPlayerName("학생 이름을 입력하세요.");
diff --git a/src/web/module/maestro_section_login.html b/src/web/module/maestro_section_login.html
index 077d27c..f5921c6 100644
--- a/src/web/module/maestro_section_login.html
+++ b/src/web/module/maestro_section_login.html
@@ -10,8 +10,8 @@ $(document).ready(function() {
 });
 
 function login() {
-	let name = $("#maestro_name").val();
-	let password = $("#password").val();
+	var name = $("#maestro_name").val();
+	var password = $("#password").val();
 
 	if(name.length === 0) {
 		showErrorMessage("아이디를 입력해 주세요.", "error");
@@ -37,7 +37,7 @@ function login() {
 		(function(errorMessage, errorCode) {
 			console.log("errorCode : " + errorCode);
 
-			let errorType = "error";
+			var errorType = "error";
 			switch(errorCode) {
 				case "not_registered_id":
 				$("#maestro_name").val("");
diff --git a/src/web/module/maestro_section_mouse_app.html b/src/web/module/maestro_section_mouse_app.html
index 1d8bdf0..2203615 100644
--- a/src/web/module/maestro_section_mouse_app.html
+++ b/src/web/module/maestro_section_mouse_app.html
@@ -5,7 +5,7 @@ $(document).ready(function() {
 });
 
 function loadMouseApp() {
-	let self = this;
+	var self = this;
 
 	sendRequestServer(	//url, sendParams, onSuccess, onFail, isDebugMode);
 		"./../server/app/mouse_app_list.php",
@@ -26,8 +26,8 @@ function loadMouseApp() {
 function makeMouseAppList(appList) {
 	$("#mouse_app_content").empty();
 
-	for(let i = 0; i < appList.length; i++) {
-		let appData = appList[i];
+	for(var i = 0; i < appList.length; i++) {
+		var appData = appList[i];
 
 		$("#mouse_app_content").append('\
 				<div class="form-check col col-sm-2">\
@@ -50,10 +50,10 @@ function makeMouseAppList(appList) {
 }
 
 function activateMouseApp(activatedList) {
-	for(let i = 0; i < activatedList.length; i++) {
-		let activatedAppID = activatedList[i].appID;
+	for(var i = 0; i < activatedList.length; i++) {
+		var activatedAppID = activatedList[i].appID;
 
-		let input = $("#" + activatedAppID);
+		var input = $("#" + activatedAppID);
 		input.prop("checked", true);
 	}
 }
diff --git a/src/web/module/maestro_section_search.html b/src/web/module/maestro_section_search.html
index 116ac9c..ff79823 100644
--- a/src/web/module/maestro_section_search.html
+++ b/src/web/module/maestro_section_search.html
@@ -21,7 +21,7 @@ $(document).ready(function() {
 
 
 function searchPlayer() {
-	let playerName = $("#search_name").val();
+	var playerName = $("#search_name").val();
 
 	if(playerName.length === 0) {
 		$("#search_name").focus();
diff --git a/src/web/module/maestro_setup.html b/src/web/module/maestro_setup.html
index 533b049..4f361f3 100644
--- a/src/web/module/maestro_setup.html
+++ b/src/web/module/maestro_setup.html
@@ -1,17 +1,17 @@
 ﻿<script>
 
-let isChangedIDName = false;
-let isAvailableIDName = false;
-let registeredMaestroIDName = "";
-let registeredEmail = "";
-let registeredPassword = "";
-let registeredAccountType = -1;
+var isChangedIDName = false;
+var isAvailableIDName = false;
+var registeredMaestroIDName = "";
+var registeredEmail = "";
+var registeredPassword = "";
+var registeredAccountType = -1;
 
-let newMaestroIDName = "";
-let newEmail = "";
+var newMaestroIDName = "";
+var newEmail = "";
 
-let newPassword = "";
-let newPasswordVerify = "";
+var newPassword = "";
+var newPasswordVerify = "";
 
 
 $(document).ready(function() {
diff --git a/src/web/module/maestro_upgrade.html b/src/web/module/maestro_upgrade.html
index 6c42401..7f328a5 100644
--- a/src/web/module/maestro_upgrade.html
+++ b/src/web/module/maestro_upgrade.html
@@ -1,6 +1,6 @@
 ﻿<script>
 
-let registeredAccountType = -1;
+var registeredAccountType = -1;
 
 
 $(document).ready(function() {
@@ -147,7 +147,7 @@ function setCardConent(cardNo, cardType) {
 
 function upgradeMaestroInfo(accountType) {
 	console.log("upgrade to " + accountType);
-	let upgradeAccountType = accountType;
+	var upgradeAccountType = accountType;
 
 	sendRequestServer(	//url, sendParams, onSuccess, onFail, isDebugMode);
 		"./../server/maestro/request_upgrade_maestro.php",
