421 4.7.32: from domain not aligned, rate limited
Gmail is rate limiting your mail because the domain in its From address matches neither the domain that passed SPF nor the one that signed DKIM.
- Gmail
- Provider
- Temporary (4xx)
- Class
- Sources checked
- Author
At a glance
- Code
- 421 4.7.32
- Provider
- Gmail and Google Workspace
- Temporary or permanent
- TemporaryThe sending server keeps the message and tries again later.
- Who has to act
- The sender. The fix is on the sending side: your domain, your server or your list.
- What the server says
421 4.7.32 …isn't aligned with either the authenticated SPF or DKIM organizational domain.
What it means
This is about DMARC alignment: the domain that passes SPF or DKIM has to share an organizational domain with the From address readers see. Your message authenticated, but only for some other domain, such as your sending provider's bounce domain or its default DKIM signature. Google's sender guidelines require bulk senders to align the From domain with SPF or DKIM, and fixing either one is enough. This is the temporary form, also listed in Google's sender guidelines FAQ. Google's SMTP reference prints the blocking form as 421 5.7.32, which has its own entry.
Common causes
- A sending provider's default DKIM signature on its own domain instead of yours.
- An envelope sender (Return-Path) on the provider's domain, so SPF passes for them and not for you.
- A From address on a domain that none of your sending services authenticate.
How to fix it
- 01Read the Authentication-Results header of a test message to Gmail and compare the SPF and DKIM domains with your From domain.
- 02Set up DKIM at your sending provider with your own domain as d=.
- 03Or set a custom Return-Path on a subdomain of your From domain so SPF aligns.
- 04Check the result with a DMARC lookup and a fresh test message.
Sources
What this page rests on, checked on 20 Oct 2026. The explanation is ours; the reply text is the server's.
- Gmail SMTP errors and codes (Google Workspace Admin Help)knowledge.workspace.google.com
- Email sender guidelines FAQ (Gmail Help)support.google.com
- Email sender guidelines (Gmail Help)support.google.com
Related codes
- 5.7.32From domain not aligned, blocked.Gmail blocked your message because the domain in its From address aligns with neither the domain that passed SPF nor the domain that signed DKIM.
- 550 5.7.26Rejected under the sender's DMARC policy.Gmail rejected the message because it failed DMARC, and the From domain's DMARC policy tells receivers to refuse mail that fails.
- 421Service not available.The receiving server is closing the connection and will not take mail right now. The reply is temporary, so the sending server keeps the message and tries again later.
Further reading
All 108 Gmail codesEvery code in the wikiPaste your own bounce