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Bounce Decoder: 452 4.2.2

SPF, DKIM, DMARC, FCrDNS, Blacklists & Inbox Prediction

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452 4.2.2 — Mailbox Full (Temporary)

The 452 4.2.2 soft bounce means the recipient mailbox is over quota right now. Learn when to retry and when to treat the address as inactive.

🟡
Temporary Failure (Soft Bounce)
SMTP Code
452
Enhanced Code
4.2.2
Category
Mailbox Full (Temporary)
Frequency
Very Common

🔢 Enhanced Status Code Breakdown: 4.2.2

Component Value Meaning
Class 4 Persistent transient failure (temporary)
Subject 2 Mailbox status
Detail 2 Mailbox Full (Temporary)

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

💬 What This Error Means

The recipient's mailbox is over its storage quota right now. This is a temporary condition that should resolve once they clear out old emails.

Common Causes

  • Recipient hasn't deleted old emails and hit their quota
  • Low storage allocation on a free or legacy account

How to Fix This

  • Wait a few days and retry
  • Notify the recipient through another channel if possible
  • If the address bounces with this code for weeks, treat it as inactive

🏢 Provider-Specific Variations

Google Workspace / Gmail

Google returns 452 4.2.2 for over-quota mailboxes, which your server will retry automatically.

📖 Google Workspace / Gmail documentation →

📋 Real-World Example Messages

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

452 4.2.2 The email account that you tried to reach is over quota. Please direct the recipient to https://support.google.com/mail/?p=OverQuota

🔗 Related Error Codes

552 5.2.2
Mailbox Over Quota
450 4.2.1
Rate Limit: Try Again Later

📚 Official Documentation

↗ Google Workspace SMTP errors
🔍

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