5.x.x permanent failure
SMTP Error Code 540: Meaning, Causes and How to Fix It
SMTP 540 is a permanent failure.
A permanent failure some providers return when the recipient's account has been suspended or deactivated. The address will not accept mail again unless that account is restored.
- Class
- 5xx permanent
- Bounce type
- Hard bounce
- Highest severity
- Varies
- Responses on record
- 2
RamblerSMTP 540 responses from email providers
How mailbox providers phrase a 540. Open a provider for the full text, severity and fix for every variation.
SMTP 540 questions
›Is SMTP 540 a hard bounce or a soft bounce?
It is a permanent failure, so a hard bounce. The receiving server will not accept the same message on a retry, and the address or the sending problem has to be fixed before you resend.
›What causes an SMTP 540 error?
A permanent failure some providers return when the recipient's account has been suspended or deactivated. The address will not accept mail again unless that account is restored. The exact reason varies by receiver, which is why this page lists the specific 540 responses recorded for Rambler.
›How do I fix an SMTP 540 bounce?
Read the enhanced status code and the message text, not just the number. Wording that names the recipient (user unknown, mailbox unavailable) means correct or remove the address. Wording that names authentication or reputation (SPF, DKIM, DMARC, blocklist) means fix that on the sending side, or clear the listing. Every response on this page has its own guidance.