452 4.2.2 Mailbox full / over quota
The recipient's mailbox has no room for the message. The server returns a 4 because the situation can change the moment the person deletes something, so your MTA will retry for a day or two before giving up. Some servers, Dovecot among them, return the permanent 552 5.2.2 "Quota exceeded" form instead.
What the server replies
452 4.2.2 <ben.wright@example.com> Mailbox full
- Sent by
- Any mail server
- Type
- TemporaryRetry helps
- About
- Recipient problems
- Enhanced code
- 4.2.2
Who sends it
Any server with mailbox quotas: Dovecot via LMTP, Exchange ("452 4.2.2 The mailbox is full"), Zimbra, cPanel hosts. The same condition from Gmail reads 552 5.2.2 "The email account that you tried to reach is over quota".
Why it happens
- The recipient has not cleaned the mailbox in a long time.
- A small hosting quota (a few hundred megabytes on some shared hosts).
- The mailbox is abandoned and has been filling up.
- A large attachment in your message is what tips it over.
How to fix it
Let it retry briefly
A day of retries costs nothing. If the person is active they will notice their mailbox is full and clear it.
Reach the recipient another way
For anything urgent, send to another address or call. They need to delete mail or ask their host for more space.
Send a link instead of a file
Resend with the attachment replaced by a download link; a small message may fit where a large one did not.
Suppress after repeated failures
An address that returns mailbox full for weeks is effectively dead. Stop sending to it to protect your reputation.
Related codes
- 552 5.2.2 The email account that you tried to reach is over quotaThe recipient's Google storage is full, so Gmail cannot accept new mail for them.
- 552 5.3.4 Message size exceeds fixed maximum message sizeThe message is larger than the receiving server allows.
- 554 5.2.0 STOREDRV.Deliver; delivery result bannerThe message was accepted by Exchange Online and then failed while being written into the recipient's mailbox.
Sources
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