diff --git a/CHANGELOG.md b/CHANGELOG.md
index ba307ece9..ca41d016c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,9 +2,17 @@ ChangeLog (Release Notes)
 =========================
 主に notable な changes を書いていきます
 
+2747 (2017/10/25)
+-----------------
+* Fix: 非ログイン状態ですべてのページが致命的な問題を発生させる (#89)
+
+2742 (2017/10/25)
+-----------------
+* New: トラブルシューティングを実装するなど
+
 2735 (2017/10/22)
 -----------------
-* モバイル版からでもクライアントバージョンを確認できるように
+* New: モバイル版からでもクライアントバージョンを確認できるように
 
 2732 (2017/10/22)
 -----------------
diff --git a/locales/en.yml b/locales/en.yml
index d4dfbf76b..03d5306d3 100644
--- a/locales/en.yml
+++ b/locales/en.yml
@@ -1,4 +1,6 @@
 common:
+  misskey: "Note everything and share it others using Misskey."
+
   time:
     unknown: "unknown"
     future: "future"
@@ -66,6 +68,25 @@ common:
       title: "Unable to connect to the server"
       description: "There is a problem with Internet connection, or the server may be down or maintaining. Please {try again} later."
       thanks: "Thank you for using Misskey."
+      troubleshoot: "Troubleshoot"
+
+      troubleshooter:
+        title: "TroubleShooting"
+        network: "Network connection"
+        checking-network: "Checking network connection"
+        internet: "Internet connection"
+        checking-internet: "Checking internet connection"
+        server: "Server connection"
+        checking-server: "Checking server connection"
+        finding: "Finding a problem"
+        no-network: "There is no Network connection"
+        no-network-desc: "Please make sure you are connected to the Network."
+        no-internet: "There is no Internet connection"
+        no-internet-desc: "Please make sure you are connected to the Internet."
+        no-server: "Unable to connect to the server"
+        no-server-desc: "The network connection of your PC is normal, but you could not connect to Misskey's server. There is a possibility that the server is down or maintaining, please try to access it again after a while."
+        success: "Successfully connect to the Misskey's server"
+        success-desc: "It seems to be able to connect normally. Please reload the page."
 
     mk-forkit:
       open-github-link: "View source on Github"
diff --git a/locales/ja.yml b/locales/ja.yml
index 9a8490dec..b640f0f24 100644
--- a/locales/ja.yml
+++ b/locales/ja.yml
@@ -1,4 +1,6 @@
 common:
+  misskey: "Misskeyに何でも投稿して皆と共有しましょう。"
+
   time:
     unknown: "なぞのじかん"
     future: "未来"
@@ -66,6 +68,25 @@ common:
       title: "サーバーに接続できません"
       description: "インターネット回線に問題があるか、サーバーがダウンまたはメンテナンスしている可能性があります。しばらくしてから{再度お試し}ください。"
       thanks: "いつもMisskeyをご利用いただきありがとうございます。"
+      troubleshoot: "トラブルシュート"
+
+      troubleshooter:
+        title: "トラブルシューティング"
+        network: "ネットワーク接続"
+        checking-network: "ネットワーク接続を確認中"
+        internet: "インターネット接続"
+        checking-internet: "インターネット接続を確認中"
+        server: "サーバー接続"
+        checking-server: "サーバー接続を確認中"
+        finding: "問題を調べています"
+        no-network: "ネットワークに接続されていません"
+        no-network-desc: "お使いのPCのネットワーク接続が正常か確認してください。"
+        no-internet: "インターネットに接続されていません"
+        no-internet-desc: "ネットワークには接続されていますが、インターネットには接続されていないようです。お使いのPCのインターネット接続が正常か確認してください。"
+        no-server: "Misskeyのサーバーに接続できません"
+        no-server-desc: "お使いのPCのネットワーク接続は正常ですが、Misskeyのサーバーには接続できませんでした。サーバーがダウンまたはメンテナンスしている可能性があるので、しばらくしてから再度御アクセスください。"
+        success: "Misskeyのサーバーに接続できました"
+        success-desc: "正常に接続できるようです。ページを再度読み込みしてください。"
 
     mk-forkit:
       open-github-link: "View source on Github"
diff --git a/package.json b/package.json
index 4ddb3cb45..43a015961 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "misskey",
   "author": "syuilo <i@syuilo.com>",
-  "version": "0.0.2735",
+  "version": "0.0.2747",
   "license": "MIT",
   "description": "A miniblog-based SNS",
   "bugs": "https://github.com/syuilo/misskey/issues",
diff --git a/src/web/app/common/tags/error.tag b/src/web/app/common/tags/error.tag
index 7a2976541..62f4563e5 100644
--- a/src/web/app/common/tags/error.tag
+++ b/src/web/app/common/tags/error.tag
@@ -8,6 +8,8 @@
 	}</a>{
 		'%i18n:common.tags.mk-error.description%'.substr('%i18n:common.tags.mk-error.description%'.indexOf('}') + 1)
 	}</p>
+	<button if={ !troubleshooting } onclick={ troubleshoot }>%i18n:common.tags.mk-error.troubleshoot%</button>
+	<mk-troubleshooter if={ troubleshooting }/>
 	<p class="thanks">%i18n:common.tags.mk-error.thanks%</p>
 	<style>
 		:scope
@@ -36,6 +38,25 @@
 				font-size 1em
 				color #666
 
+			> button
+				display block
+				margin 1em auto 0 auto
+				padding 8px 10px
+				color $theme-color-foreground
+				background $theme-color
+
+				&:focus
+					outline solid 3px rgba($theme-color, 0.3)
+
+				&:hover
+					background lighten($theme-color, 10%)
+
+				&:active
+					background darken($theme-color, 10%)
+
+			> mk-troubleshooter
+				margin 1em auto 0 auto
+
 			> .thanks
 				display block
 				margin 2em auto 0 auto
@@ -55,6 +76,8 @@
 
 	</style>
 	<script>
+		this.troubleshooting = false;
+
 		this.on('mount', () => {
 			document.title = 'Oops!';
 			document.documentElement.style.background = '#f8f8f8';
@@ -63,5 +86,132 @@
 		this.reload = () => {
 			location.reload();
 		};
+
+		this.troubleshoot = () => {
+			this.update({
+				troubleshooting: true
+			});
+		};
 	</script>
 </mk-error>
+
+<mk-troubleshooter>
+	<h1><i class="fa fa-wrench"></i>%i18n:common.tags.mk-error.troubleshooter.title%</h1>
+	<div>
+		<p data-wip={ network == null }><i if={ network != null } class="fa fa-{ network ? 'check' : 'times' }"></i>{ network == null ? '%i18n:common.tags.mk-error.troubleshooter.checking-network%' : '%i18n:common.tags.mk-error.troubleshooter.network%' }<mk-ellipsis if={ network == null }/></p>
+		<p if={ network == true } data-wip={ internet == null }><i if={ internet != null } class="fa fa-{ internet ? 'check' : 'times' }"></i>{ internet == null ? '%i18n:common.tags.mk-error.troubleshooter.checking-internet%' : '%i18n:common.tags.mk-error.troubleshooter.internet%' }<mk-ellipsis if={ internet == null }/></p>
+		<p if={ internet == true } data-wip={ server == null }><i if={ server != null } class="fa fa-{ server ? 'check' : 'times' }"></i>{ server == null ? '%i18n:common.tags.mk-error.troubleshooter.checking-server%' : '%i18n:common.tags.mk-error.troubleshooter.server%' }<mk-ellipsis if={ server == null }/></p>
+	</div>
+	<p if={ !end }>%i18n:common.tags.mk-error.troubleshooter.finding%<mk-ellipsis/></p>
+	<p if={ network === false }><b><i class="fa fa-exclamation-triangle"></i>%i18n:common.tags.mk-error.troubleshooter.no-network%</b><br>%i18n:common.tags.mk-error.troubleshooter.no-network-desc%</p>
+	<p if={ internet === false }><b><i class="fa fa-exclamation-triangle"></i>%i18n:common.tags.mk-error.troubleshooter.no-internet%</b><br>%i18n:common.tags.mk-error.troubleshooter.no-internet-desc%</p>
+	<p if={ server === false }><b><i class="fa fa-exclamation-triangle"></i>%i18n:common.tags.mk-error.troubleshooter.no-server%</b><br>%i18n:common.tags.mk-error.troubleshooter.no-server-desc%</p>
+	<p if={ server === true } class="success"><b><i class="fa fa-info-circle"></i>%i18n:common.tags.mk-error.troubleshooter.success%</b><br>%i18n:common.tags.mk-error.troubleshooter.success-desc%</p>
+
+	<style>
+		:scope
+			display block
+			width 100%
+			max-width 500px
+			text-align left
+			background #fff
+			border-radius 8px
+			border solid 1px #ddd
+
+			> h1
+				margin 0
+				padding 0.6em 1.2em
+				font-size 1em
+				color #444
+				border-bottom solid 1px #eee
+
+				> i
+					margin-right 0.25em
+
+			> div
+				overflow hidden
+				padding 0.6em 1.2em
+
+				> p
+					margin 0.5em 0
+					font-size 0.9em
+					color #444
+
+					&[data-wip]
+						color #888
+
+					> i
+						margin-right 0.25em
+
+						&.fa-times
+							color #e03524
+
+						&.fa-check
+							color #84c32f
+
+			> p
+				margin 0
+				padding 0.6em 1.2em
+				font-size 1em
+				color #444
+				border-top solid 1px #eee
+
+				> b
+					> i
+						margin-right 0.25em
+
+				&.success
+					> b
+						color #39adad
+
+				&:not(.success)
+					> b
+						color #ad4339
+
+	</style>
+	<script>
+		import CONFIG from '../../common/scripts/config';
+
+		this.on('mount', () => {
+			this.update({
+				network: navigator.onLine
+			});
+
+			if (!this.network) {
+				this.update({
+					end: true
+				});
+				return;
+			}
+
+			// Check internet connection
+			fetch('https://google.com?rand=' + Math.random(), {
+				mode: 'no-cors'
+			}).then(() => {
+				this.update({
+					internet: true
+				});
+
+				// Check misskey server is available
+				fetch(`${CONFIG.apiUrl}/meta`).then(() => {
+					this.update({
+						end: true,
+						server: true
+					});
+				})
+				.catch(() => {
+					this.update({
+						end: true,
+						server: false
+					});
+				});
+			})
+			.catch(() => {
+				this.update({
+					end: true,
+					internet: false
+				});
+			});
+		});
+	</script>
+</mk-troubleshooter>
diff --git a/src/web/app/desktop/tags/home-widgets/version.tag b/src/web/app/desktop/tags/home-widgets/version.tag
index fa92afc49..ea5307061 100644
--- a/src/web/app/desktop/tags/home-widgets/version.tag
+++ b/src/web/app/desktop/tags/home-widgets/version.tag
@@ -1,5 +1,5 @@
 <mk-version-home-widget>
-	<p>ver { version }</p>
+	<p>ver { version } (葵 aoi)</p>
 	<style>
 		:scope
 			display block
diff --git a/src/web/app/desktop/tags/timeline.tag b/src/web/app/desktop/tags/timeline.tag
index cd7ac7d20..2d6b439e3 100644
--- a/src/web/app/desktop/tags/timeline.tag
+++ b/src/web/app/desktop/tags/timeline.tag
@@ -424,6 +424,7 @@
 		import compile from '../../common/scripts/text-compiler';
 		import dateStringify from '../../common/scripts/date-stringify';
 
+		this.mixin('i');
 		this.mixin('api');
 		this.mixin('stream');
 		this.mixin('user-preview');
@@ -462,24 +463,31 @@
 		};
 
 		this.capture = withHandler => {
-			this.stream.send({
-				type: 'capture',
-				id: this.post.id
-			});
-			if (withHandler) this.stream.on('post-updated', this.onStreamPostUpdated);
+			if (this.SIGNIN) {
+				this.stream.send({
+					type: 'capture',
+					id: this.post.id
+				});
+				if (withHandler) this.stream.on('post-updated', this.onStreamPostUpdated);
+			}
 		};
 
 		this.decapture = withHandler => {
-			this.stream.send({
-				type: 'decapture',
-				id: this.post.id
-			});
-			if (withHandler) this.stream.off('post-updated', this.onStreamPostUpdated);
+			if (this.SIGNIN) {
+				this.stream.send({
+					type: 'decapture',
+					id: this.post.id
+				});
+				if (withHandler) this.stream.off('post-updated', this.onStreamPostUpdated);
+			}
 		};
 
 		this.on('mount', () => {
 			this.capture(true);
-			this.stream.on('_connected_', this.onStreamConnected);
+
+			if (this.SIGNIN) {
+				this.stream.on('_connected_', this.onStreamConnected);
+			}
 
 			if (this.p.text) {
 				const tokens = this.p.ast;
diff --git a/src/web/app/desktop/tags/ui.tag b/src/web/app/desktop/tags/ui.tag
index fce0743ff..e0d7393b0 100644
--- a/src/web/app/desktop/tags/ui.tag
+++ b/src/web/app/desktop/tags/ui.tag
@@ -5,7 +5,7 @@
 	<div class="content">
 		<yield />
 	</div>
-	<mk-stream-indicator/>
+	<mk-stream-indicator if={ SIGNIN }/>
 	<style>
 		:scope
 			display block
@@ -416,22 +416,26 @@
 		this.page = this.opts.page;
 
 		this.on('mount', () => {
-			this.stream.on('read_all_messaging_messages', this.onReadAllMessagingMessages);
-			this.stream.on('unread_messaging_message', this.onUnreadMessagingMessage);
+			if (this.SIGNIN) {
+				this.stream.on('read_all_messaging_messages', this.onReadAllMessagingMessages);
+				this.stream.on('unread_messaging_message', this.onUnreadMessagingMessage);
 
-			// Fetch count of unread messaging messages
-			this.api('messaging/unread').then(res => {
-				if (res.count > 0) {
-					this.update({
-						hasUnreadMessagingMessages: true
-					});
-				}
-			});
+				// Fetch count of unread messaging messages
+				this.api('messaging/unread').then(res => {
+					if (res.count > 0) {
+						this.update({
+							hasUnreadMessagingMessages: true
+						});
+					}
+				});
+			}
 		});
 
 		this.on('unmount', () => {
-			this.stream.off('read_all_messaging_messages', this.onReadAllMessagingMessages);
-			this.stream.off('unread_messaging_message', this.onUnreadMessagingMessage);
+			if (this.SIGNIN) {
+				this.stream.off('read_all_messaging_messages', this.onReadAllMessagingMessages);
+				this.stream.off('unread_messaging_message', this.onUnreadMessagingMessage);
+			}
 		});
 
 		this.onReadAllMessagingMessages = () => {
diff --git a/src/web/app/init.js b/src/web/app/init.js
index 44391b8fc..cb661c259 100644
--- a/src/web/app/init.js
+++ b/src/web/app/init.js
@@ -2,7 +2,7 @@
  * App initializer
  */
 
-"use strict";
+'use strict';
 
 import * as riot from 'riot';
 import api from './common/scripts/api';
@@ -19,7 +19,15 @@ require('./common/tags');
  * APP ENTRY POINT!
  */
 
-console.info(`Misskey v${VERSION}`);
+console.info(`Misskey v${VERSION} (葵 aoi)`);
+
+{ // Set description meta tag
+	const head = document.getElementsByTagName('head')[0];
+	const meta = document.createElement('meta');
+	meta.setAttribute('name', 'description');
+	meta.setAttribute('content', '%i18n:common.misskey%');
+	head.appendChild(meta);
+}
 
 document.domain = CONFIG.host;
 
diff --git a/src/web/app/mobile/tags/page/settings.tag b/src/web/app/mobile/tags/page/settings.tag
index b366d3a16..b6501142e 100644
--- a/src/web/app/mobile/tags/page/settings.tag
+++ b/src/web/app/mobile/tags/page/settings.tag
@@ -29,7 +29,7 @@
 	<ul>
 		<li><a onclick={ signout }><i class="fa fa-power-off"></i>%i18n:mobile.tags.mk-settings-page.signout%</a></li>
 	</ul>
-	<p><small>ver { version }</small></p>
+	<p><small>ver { version } (葵 aoi)</small></p>
 	<style>
 		:scope
 			display block
diff --git a/src/web/app/mobile/tags/timeline.tag b/src/web/app/mobile/tags/timeline.tag
index 5ecc2df9d..c7f5bfd68 100644
--- a/src/web/app/mobile/tags/timeline.tag
+++ b/src/web/app/mobile/tags/timeline.tag
@@ -467,6 +467,7 @@
 		import getPostSummary from '../../../../common/get-post-summary.ts';
 		import openPostForm from '../scripts/open-post-form';
 
+		this.mixin('i');
 		this.mixin('api');
 		this.mixin('stream');
 
@@ -502,24 +503,31 @@
 		};
 
 		this.capture = withHandler => {
-			this.stream.send({
-				type: 'capture',
-				id: this.post.id
-			});
-			if (withHandler) this.stream.on('post-updated', this.onStreamPostUpdated);
+			if (this.SIGNIN) {
+				this.stream.send({
+					type: 'capture',
+					id: this.post.id
+				});
+				if (withHandler) this.stream.on('post-updated', this.onStreamPostUpdated);
+			}
 		};
 
 		this.decapture = withHandler => {
-			this.stream.send({
-				type: 'decapture',
-				id: this.post.id
-			});
-			if (withHandler) this.stream.off('post-updated', this.onStreamPostUpdated);
+			if (this.SIGNIN) {
+				this.stream.send({
+					type: 'decapture',
+					id: this.post.id
+				});
+				if (withHandler) this.stream.off('post-updated', this.onStreamPostUpdated);
+			}
 		};
 
 		this.on('mount', () => {
 			this.capture(true);
-			this.stream.on('_connected_', this.onStreamConnected);
+
+			if (this.SIGNIN) {
+				this.stream.on('_connected_', this.onStreamConnected);
+			}
 
 			if (this.p.text) {
 				const tokens = this.p.ast;
diff --git a/src/web/app/mobile/tags/ui.tag b/src/web/app/mobile/tags/ui.tag
index b2f738dc2..9d9cd4d74 100644
--- a/src/web/app/mobile/tags/ui.tag
+++ b/src/web/app/mobile/tags/ui.tag
@@ -4,7 +4,7 @@
 	<div class="content">
 		<yield />
 	</div>
-	<mk-stream-indicator/>
+	<mk-stream-indicator if={ SIGNIN }/>
 	<style>
 		:scope
 			display block
diff --git a/webpack/module/rules/i18n.ts b/webpack/module/rules/i18n.ts
index 3023253ca..9a4acde68 100644
--- a/webpack/module/rules/i18n.ts
+++ b/webpack/module/rules/i18n.ts
@@ -4,34 +4,46 @@
 
 const StringReplacePlugin = require('string-replace-webpack-plugin');
 
-export default (lang, locale) => ({
-	enforce: 'pre',
-	test: /\.(tag|js)$/,
-	exclude: /node_modules/,
-	loader: StringReplacePlugin.replace({
-		replacements: [
-			{
-				pattern: /%i18n:(.+?)%/g, replacement: (_, key) => {
-					let text = locale;
-					
-					// Check the key existance
-					const error = key.split('.').some(k => {
-						if (text.hasOwnProperty(k)) {
-							text = text[k];
-							return false;
-						} else {
-							return true;
-						}
-					});
-					
-					if (error) {
-						console.warn(`key '${key}' not found in '${lang}'`);
-						return key; // Fallback
-					} else {
-						return text.replace(/'/g, '\\\'').replace(/"/g, '\\"');
-					}
-				}
+export default (lang, locale) => {
+	function get(key: string) {
+		let text = locale;
+
+		// Check the key existance
+		const error = key.split('.').some(k => {
+			if (text.hasOwnProperty(k)) {
+				text = text[k];
+				return false;
+			} else {
+				return true;
 			}
-		]
-	})
-});
+		});
+
+		if (error) {
+			console.warn(`key '${key}' not found in '${lang}'`);
+			return key; // Fallback
+		} else {
+			return text;
+		}
+	}
+
+	return {
+		enforce: 'pre',
+		test: /\.(tag|js)$/,
+		exclude: /node_modules/,
+		loader: StringReplacePlugin.replace({
+			replacements: [{
+				pattern: /"%i18n:(.+?)%"/g, replacement: (_, key) => {
+					return '"' + get(key).replace(/"/g, '\\"') + '"';
+				}
+			}, {
+				pattern: /'%i18n:(.+?)%'/g, replacement: (_, key) => {
+					return '\'' + get(key).replace(/'/g, '\\\'') + '\'';
+				}
+			}, {
+				pattern: /%i18n:(.+?)%/g, replacement: (_, key) => {
+					return get(key);
+				}
+			}]
+		})
+	};
+};