diff --git a/locales/ja-JP.yml b/locales/ja-JP.yml
index 6c4a821d35..62b2ddf004 100644
--- a/locales/ja-JP.yml
+++ b/locales/ja-JP.yml
@@ -1134,7 +1134,8 @@ admin/views/instance.vue:
   email-config-info: "メールアドレス確認やパスワードリセットの際に使われます。"
   enable-email: "メール配信を有効にする"
   email: "メールアドレス"
-  smtp-use-ssl: "SMTPサーバーはSSLを使用"
+  smtp-secure: "SMTP接続に暗黙的なSSL/TLSを使用する"
+  smtp-secure-info: "STARTTLS使用時はオフにします。"
   smtp-host: "SMTPホスト"
   smtp-port: "SMTPポート"
   smtp-user: "SMTPユーザー"
diff --git a/src/client/app/admin/views/instance.vue b/src/client/app/admin/views/instance.vue
index 8609abf1e5..05de9b1c06 100644
--- a/src/client/app/admin/views/instance.vue
+++ b/src/client/app/admin/views/instance.vue
@@ -52,7 +52,7 @@
 				<ui-input v-model="smtpUser" :disabled="!enableEmail">{{ $t('smtp-user') }}</ui-input>
 				<ui-input v-model="smtpPass" :disabled="!enableEmail">{{ $t('smtp-pass') }}</ui-input>
 			</ui-horizon-group>
-			<ui-switch v-model="smtpSecure" :disabled="!enableEmail">{{ $t('smtp-use-ssl') }}</ui-switch>
+			<ui-switch v-model="smtpSecure" :disabled="!enableEmail">{{ $t('smtp-secure') }}<span slot="desc">{{ $t('smtp-secure-info') }}</span></ui-switch>
 		</section>
 		<section>
 			<header>summaly Proxy</header>
diff --git a/src/server/api/endpoints/i/update_email.ts b/src/server/api/endpoints/i/update_email.ts
index 0aa22b4d83..b5bff048cc 100644
--- a/src/server/api/endpoints/i/update_email.ts
+++ b/src/server/api/endpoints/i/update_email.ts
@@ -73,10 +73,11 @@ export default define(meta, (ps, user) => new Promise(async (res, rej) => {
 			host: meta.smtpHost,
 			port: meta.smtpPort,
 			secure: meta.smtpSecure,
-			auth: {
+			ignoreTLS: true,
+			auth: meta.smtpUser != null ? {
 				user: meta.smtpUser,
 				pass: meta.smtpPass
-			}
+			} : undefined
 		});
 
 		const link = `${config.url}/vefify-email/${code}`;