退信

• 退信提示："Can not send mail with this COS"
• 退信提示："550 Domain frequency limited"
• 退信提示："550 Mail content denied"
• 退信提示："SMTP error, RCPT TO：551 5.7.1 Go away!"
• 退信提示："SMTP error, OPEN：550 Denied by policy"
• 退信提示："SMTP error, DOT：554 sorry, Spam detected by SpamAssassin (#5.3.4)."
• 退信提示："SMTP error, DOT：554 Transaction Failed"
• 退信提示："SMTP error, DOT： 553 5.7.3 CONTENT REJECT"
• 退信提示："DOT：554 this mail is rejected by antispam system"
• 退信提示："554 Denied (Mode：normal）"
• 退信提示："554 5.6.0 Invalid content"
• 退信提示："SMTP error, DOT：519 Rejected."
• 退信提示："MAIL FROM： 550 5.0.0 Mail rejected due to possible SPAM"
• 退信提示："SMTP error, RCPT TO：550 Use mail relays of your ISP.."
• 退信提示："550 5.7.1 Recipient not authorized, your IP has been found on a block list"