Gmail 421 5.7.32
Blocked: From not aligned
Gmail 421 5.7.32 means: blocked: From not aligned. It is a temporary failure, so your server retries it. Gmail lists this permanent enhanced code with a 421 reply. Align the From domain with the SPF or DKIM domain before resending; retrying unchanged will not help.
Gmail’s exact wording
Quoted from Google Workspace Admin Help: Gmail SMTP errors and codes, checked 2026-11-05. Placeholders are Gmail’s own.
Reply text
Your email was blocked because the From: header (RFC5322) in this message isn't aligned with either the authenticated SPF or DKIM organizational domain. Learn more about DMARC alignment. To learn more about Gmail requirements for bulk email senders, visit Email sender guidelines.
| Who sends it | Gmail and Google Workspace |
|---|---|
| Basic code | 421: <domain> Service not available, closing transmission channel (RFC) |
| Enhanced code | 5.7.32: Gmail-specific, not in the IANA registry. Its subject digit puts it under 5.7.0 other or undefined security status. |
| Permanent or temporary | Temporary (4xx) |
| Verifying the list prevents it | No |
What the sender should do
Gmail lists this permanent enhanced code with a 421 reply. Align the From domain with the SPF or DKIM domain before resending; retrying unchanged will not help.
Would verifying the list have prevented Gmail 421 5.7.32?
No
This reply is about your sending setup, the message or the receiving system, not about whether the address exists, so verifying the list will not prevent it.
Common questions
- What does Gmail 421 5.7.32 mean?
- Gmail 421 5.7.32 means: blocked: From not aligned. It is a temporary failure, so your server retries it. Gmail lists this permanent enhanced code with a 421 reply. Align the From domain with the SPF or DKIM domain before resending; retrying unchanged will not help.
- Should I retry after Gmail 421 5.7.32?
- Your sending server retries it automatically, because it is a temporary (4xx) failure. Investigate only if it keeps coming back over several hours.
- Would verifying my list have prevented Gmail 421 5.7.32?
- No. This reply is about your sending setup, the message or the receiving system, not about whether the address exists, so verifying the list will not prevent it.
Sources
- Google Workspace Admin Help: Gmail SMTP errors and codes (checked 2026-11-05)
- RFC 5321: Simple Mail Transfer Protocol, section 4.2.3 (reply codes) (checked 2026-11-05)
Registry and provider wording is quoted exactly; guidance is written by the SimpleVerifier Team.
SimpleVerifier Team · Last checked against the sources 2026-11-05