【重要】本校電子郵件伺服器於115年10月6日起關閉Open Relay功能
為提升校園網路資訊安全並符合教育部資安稽核規範，本校電子郵件伺服器於 115年10月6日起 關閉 Open Relay 功能，除申請白名單外，其餘寄信皆需使用帳號密碼驗證。此舉旨在符合教育部資安稽核規範，及防止本校電子郵件伺服器被惡意利用發送垃圾郵件，誤當成黑名單遭到封鎖，影響全校師生正常信件往來。影響範圍包含教職員工(@dragon.nchu.edu.tw,@nchu.edu.tw)及學生(@mail.nchu.edu.tw)郵件伺服器。
如果您發現無法寄信，出現⚠️ 504 Authentication failed for SMTP service 錯誤訊息，表示您的設定有誤，請參考以下說明進行確認：️
- Webmail 使用者：不受影響，無需任何動作。
- 手機/電腦郵件軟體使用者 (例如：Outlook, 手機 App)：請檢查您的軟體設定，確認「寄件伺服器 (SMTP)」已設定「帳號與密碼驗證」，若未設定，未來將無法寄信。(Outlook 及手機 相關設定教學)
- 主機/系統/ 網站管理員/網路印表機/事務機：若有使用寄信服務，並將「寄件伺服器(SMTP)」設定為本校電子郵件伺服器主機，伺服器名稱為：dragon.nchu.edu.tw 或 mail.nchu.edu.tw，請確認是否加入帳號密碼驗證。如有特殊需求無法設定驗證，請洽計資中心資訊網路組申請白名單(填寫特殊作業申請表，送至計資中心網路組)
► 詳細圖文說明與設定教學，請參閱相關網頁：https://webmail.nchu.edu.tw/or/openrelay.html
若有任何疑問，歡迎來信洽詢。
計資中心 資訊網路組 敬上
To enhance campus network information security and comply with the Ministry of Education's cybersecurity audit standards, the email server disabled the Open Relay function on October 6, 2026. Except for applying for a whitelist, all other applications require account and password verification.This measure is necessary to prevent our servers from being exploited for spam, which could lead to the email server IP address being blacklisted and disrupting normal email communications.
The scope of influence includes Faculty and Staff email (@dragon.nchu.edu.tw, @nchu.edu.tw) and Students email (@mail.nchu.edu.tw) server.
If you find that you are unable to send emails and receive the ⚠️504 Authentication failed for SMTP service message, it means that your settings are incorrect. Please refer to the following impact factors for confirmation:
- Webmail Users: No action required. You are not affected.
- Email Software/App Users (e.g., Outlook, Mobile Apps): Please check your settings. Ensure that your [SMTP Service] is configured with [Username and Password authentication]. Failure to do so will result in an inability to send emails after the deadline. (Outlook and mobile phone related settings tutorial)
- Server/System/Website Administrators/Network printer(scanner): If you use our email server [SMTP Service] to send emails via the server name dragon.nchu.edu.tw or mail.nchu.edu.tw, please confirm that account and password verification has been added to the program.
If you have special requirements that prevent you from setting up verification, please contact the Network Division of the Computer and Information Network Center to apply for a whitelist.
► For detailed instructions and setup guides, please visit: https://webmail.nchu.edu.tw/or/openrelay_en.html
If you have any questions, please feel free to contact us.
Sincerely,
Network Division, Computer and Information Network Center