diff --git a/mail_post_defer/i18n/ja.po b/mail_post_defer/i18n/ja.po
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+# Translation of Odoo Server.
+# This file contains the translation of the following modules:
+# 	* mail_post_defer
+#
+msgid ""
+msgstr ""
+"Project-Id-Version: Odoo Server 18.0\n"
+"Report-Msgid-Bugs-To: \n"
+"POT-Creation-Date: 2026-03-25 14:47+0000\n"
+"PO-Revision-Date: 2026-03-25 14:47+0000\n"
+"Last-Translator: \n"
+"Language-Team: \n"
+"MIME-Version: 1.0\n"
+"Content-Type: text/plain; charset=UTF-8\n"
+"Content-Transfer-Encoding: \n"
+"Plural-Forms: \n"
+
+#. module: mail_post_defer
+#. odoo-python
+#: code:addons/mail_post_defer/models/mail_thread.py:0
+msgid "Cannot modify message; notifications were already sent."
+msgstr "メッセージを変更できません。通知はすでに送信されています。"
+
+#. module: mail_post_defer
+#: model:ir.model,name:mail_post_defer.model_mail_thread
+msgid "Email Thread"
+msgstr "Eメールスレッド"
+
+#. module: mail_post_defer
+#: model:ir.model,name:mail_post_defer.model_mail_compose_message
+msgid "Email composition wizard"
+msgstr "メール作成ウィザード"
+
+#. module: mail_post_defer
+#: model:ir.model,name:mail_post_defer.model_mail_message
+msgid "Message"
+msgstr "メッセージ"
+
+#. module: mail_post_defer
+#. odoo-python
+#: code:addons/mail_post_defer/models/mail_thread.py:0
+msgid "Only messages type comment can have their content updated"
+msgstr "コメントタイプのメッセージのみ内容を更新できます。"
+
+#. module: mail_post_defer
+#: model:ir.model,name:mail_post_defer.model_mail_message_schedule
+msgid "Scheduled Messages"
+msgstr "送信予約済メッセージ"
+
+#. module: mail_post_defer
+#: model:ir.model.fields,field_description:mail_post_defer.field_mail_compose_message__smart_search
+#: model:ir.model.fields,field_description:mail_post_defer.field_mail_message__smart_search
+#: model:ir.model.fields,field_description:mail_post_defer.field_mail_message_schedule__smart_search
+#: model:ir.model.fields,field_description:mail_post_defer.field_mail_thread__smart_search
+msgid "Smart Search"
+msgstr "スマートサーチ"