What causes Gmail TempFail errors and how to troubleshoot them?
Summary
What email marketers say11Marketer opinions
Email marketer from Sendgrid community shares that poor IP reputation can cause more frequent TempFail errors. Use tools to check your IP reputation and take steps to improve it, such as warming up your IP address and following email best practices.
Email marketer from Port25 mentions that proper email authentication with SPF, DKIM, and DMARC is crucial. Incorrect authentication can cause mail servers to temporarily reject your emails.
Email marketer from Email Geeks explains that these are usually "transient/deferred" errors in your logs.
Email marketer from EmailGeek Forum explains that encountering "TempFail - Rate limit exceeded" often indicates you're sending emails too quickly. To troubleshoot, reduce your sending rate and gradually increase it as your reputation improves with the receiving server.
Email marketer from Quora suggests that Gmail's spam filters can sometimes trigger temporary failures if your email content is flagged as suspicious. Review your email content and subject lines to ensure they are not spammy.
Email marketer from StackOverflow suggests checking your mail server logs for specific error messages related to the TempFail. These messages often provide clues about the cause, such as connection issues or authentication problems. Also, ensure your SPF and DKIM records are correctly configured.
Email marketer from Email Geeks shares that if the connection to Gmail MTA is not being accepted, it could escape your logs. This means that your machine connection is rejected before it is established, thus the SMTP transaction does not happen.
Email marketer from Reddit mentions that greylisting is a common reason for TempFail errors. The receiving server temporarily rejects the email to filter spam, expecting a retry from a legitimate server. Ensure your server retries delivery as per SMTP standards.
Email marketer from MXToolbox Forum recommends using MXToolbox to check your email server's health. Look for any DNS issues, blacklist listings, or SMTP errors that might be contributing to temporary failures.
Email marketer from DigitalOcean's Community explains that network connectivity issues between your mail server and Gmail's servers can cause temporary failures. Check DNS settings, firewall rules, and ensure there are no routing problems preventing successful email delivery.
Email marketer from Mailjet shares that temporary failures can be caused by various reasons, including the recipient server being busy, greylisting, or temporary network issues. Troubleshooting involves checking server logs and ensuring your sending infrastructure is properly configured.
What the experts say8Expert opinions
Expert from Email Geeks shares that in the short term, you should send slower to avoid "TempFail - Rate limit exceeded" errors. In the longer term, you should build a better reputation to allow sending faster.
Expert from Email Geeks answers that rate limiting errors are likely a 4xx deferral.
Expert from Email Geeks explains that DKIM replay is sending a valid message that gets a valid DKIM signature and then sending it to a bunch of recipients through an infrastructure that doesn't add a DKIM signature so that the message has the reputation of the original signing entity.
Expert from Word to the Wise mentions that temporary delivery failures can be related to throttling by the receiving server. Monitoring sending limits and adjusting sending patterns may help prevent these issues.
Expert from Email Geeks explains that the recipient need not be in any signed field for DKIM.
Expert from Email Geeks explains that the recipient need not be in the To: field, or any visible header field for DKIM.
Expert from Spam Resource explains that temporary email delivery failures (TempFails) can occur due to temporary network issues or if the receiving server is overloaded. Checking the mail server logs for specific error codes is essential for diagnosis.
Expert from Email Geeks suggests that given GPT reporting is domain based, one possibility is that the domain is being temp failed, but the mail is not coming from your servers and could be SPF escalation version of DKIM replay.
What the documentation says4Technical articles
Documentation from Postfix.org explains proper queue management is critical for mail servers. Tempfails can occur if the queue is overloaded. Ensure your server is configured for efficient queue processing.
Documentation from Microsoft Learn notes that in Exchange Server, temporary errors can occur due to resource constraints on the receiving server (e.g., CPU or memory). Monitoring server performance and addressing bottlenecks can help resolve these issues.
Documentation from Google Workspace Admin Help explains that a temporary delivery error (TempFail) means the receiving server is temporarily unavailable. The sending server will retry delivery for a period of time.
Documentation from RFC 5321 defines SMTP reply codes; 4xx codes indicate temporary failures. The server experiencing the temporary failure determines the retry schedule.