421 4.7.0: Temporary Policy Rejection

The 421 4.7.0 soft bounce is a temporary policy rejection, often from Google. Learn what triggers it and how to fix rate limiting or new IP issues.

Published · Last verified · Maintained by TamingDNS

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Temporary Failure (Soft Bounce)
SMTP Code
421
Enhanced Code
4.7.0
Category
Temporary Policy Rejection
Frequency
Very Common

🔢 Enhanced Status Code Breakdown: 4.7.0

Component Value Meaning
Class 4 Temporary failure (Soft bounce)
Subject 7 Security or policy
Detail 0 Temporary Policy Rejection

Per RFC 3463 Enhanced Mail System Status Codes. Class (X) = severity, Subject (Y) = category, Detail (Z) = specific condition.

💬 What This Error Means

The receiving server has put your email on 'hold' for a moment. This is a temporary pause, often because you're sending from a new IP address or your reputation is still being established. It's a standard safety check used by major providers like Google.

Common Causes

  • Your sending IP address is new and doesn't have a history yet
  • You've recently increased the amount of mail you're sending
  • A temporary "spike" in your sending triggered a safety limit

How to Fix This

  • Be patient. Your mail server will automatically try again in 10-30 minutes
  • If you're sending bulk mail, make sure to spread it out over a few hours
  • If you've just moved to a new mail service, follow their "warm-up" guide to build your reputation

📚 Official Documentation

Google Workspace / Gmail

Google 421 4.7.0 is a generic temporary hold, often for new IPs or reputation concerns. Back off and retry.

📖 Google Workspace / Gmail documentation → Browse all Google Workspace / Gmail error codes →
Google Postmaster Tools

📋 Real-World Example Messages

These are real bounce message formats you might receive. Paste yours into the Bounce Decoder for instant analysis.

421 4.7.0 Try again later, closing connection
421-4.7.0 Our system has detected an unusual rate of unsolicited mail
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