What exactly does a TempFail message mean?

A TempFail is a temporary delivery failure, meaning the email server will retry sending the message. Common reasons include a recipient's mailbox being full (which is often temporary), server issues, or the email being temporarily blocked due to perceived low sender reputation or suspicious content by the receiving ISP (like Gmail).

Is the TempFail problem a Klaviyo issue or a Gmail issue?

While Klaviyo handles the sending infrastructure, the primary cause of TempFail messages often lies in your content, audience engagement, or overall sender reputation (domain and IP reputation). Shared IPs can also be a factor if other senders on the same IP are having issues. Klaviyo provides data to help diagnose these issues, but the ultimate solution often involves refining your sending strategy.

What are the first steps to troubleshoot TempFail messages?

First, check Klaviyo's bounce logs for details, especially the JSON metadata for TempFail reasons. Simultaneously, use Google Postmaster Tools to monitor your domain's reputation and delivery error trends. Look for patterns in the content, links, or audience segments that correlate with higher TempFail rates. If needed, contact Klaviyo support for detailed log analysis.

Could DMARC configuration be causing these TempFail messages?

It is unlikely to be a DMARC issue if your p=quarantine policy shows high authentication rates. DMARC failures typically manifest differently than TempFail messages, especially those flagged as suspected spam . However, ensuring SPF, DKIM, and DMARC are correctly configured across all your sending platforms is always a crucial best practice.

How do I troubleshoot delivery errors and TempFail messages in Klaviyo when using Gmail? - Troubleshooting - Email deliverability - Knowledge base

Encountering email delivery errors and TempFail messages when sending emails through

Klaviyo to

Gmail can be a frustrating experience. It suggests that your messages are not reaching their intended recipients, potentially impacting your marketing efforts and customer communication. While authentication like DMARC might seem solid, other factors often contribute to these intermittent issues, especially when using shared IP addresses.

Understanding TempFail messages

A TempFail (temporary failure) is a common email delivery status indicating that a message could not be delivered on the first attempt, but the mail server will try again later. This is different from a hard bounce, which signifies a permanent delivery failure. While some TempFail messages are benign, like a recipient's mailbox being full, others can point to deeper issues related to sender reputation or content, often flagged as suspected spam by Gmail. You can learn more about these errors and their causes by checking our dedicated guide on Gmail TempFail errors.

To identify if

Klaviyo is the source of these TempFail messages, you need to dig into your delivery logs or the bounce data provided within

Klaviyo itself. While shared IP environments might restrict direct access to server logs (like using grep to filter for gsmtp errors),

Klaviyo's interface usually provides detailed bounce reasons. If you have multiple sending platforms, isolating the source is crucial before troubleshooting. Our article on improving Gmail deliverability rates can offer a broader perspective.

Klaviyo, you can examine the metadata of bounced emails, particularly those to

Gmail addresses. This can often reveal the specific reason for the TempFail. If your

Google Postmaster Tools (GPT) account shows delivery errors, clicking on the data points in the graphs might provide additional context, such as a suspected spam reason for TempFail (or temporary failure) messages. This diagnostic approach helps narrow down the potential causes beyond simple mailbox capacity issues.

Example Gmail TempFail error messageplaintext

421 4.7.0 [.IP.Address.] Our system has detected that this message is suspicious due to the very low reputation of the sending domain. To best protect our users from spam, the message has been blocked. Please visit https://support.google.com/mail/answer/188131 for more information. qo12-20020a170907874c00b0093b053a6655si3925477ejc.34 - gsmtp

Diagnosing the root causes

A common cause of TempFail messages, especially those flagged as suspected spam, is low sender reputation. While your

Gmail Postmaster Tools might show healthy DMARC authentication rates, the issue could stem from the specific content of your emails, particular segments of your audience, or even your use of shared IP addresses through

Klaviyo. Gmail's filtering algorithms are highly sophisticated, and even minor signals can trigger temporary blocks. You can consult Google's troubleshooter for senders to find out more.

Specific elements within your email content can also trigger spam flags. This includes problematic links, overly promotional language, or even certain images. In some cases, third-party link tracking tools or domains used within your email can be blocklisted (or blacklisted), leading to delivery issues. Reviewing your email content for anything that might be perceived as spammy is an important step. Our guide on why your emails go to spam provides a detailed overview.

Although less likely for TempFail messages, DMARC alignment and configuration errors can also contribute to delivery problems. While a p=quarantine policy and high authentication rates are good, any inconsistencies in your DMARC, SPF, or DKIM setup could cause issues. For instance, if you're signing with a different domain (d=) from other sending sources, it might confuse recipients and filters. This is especially relevant with the new Google and Yahoo requirements for bulk senders. Our simple guide to DMARC, SPF, and DKIM can help clarify these protocols.

Understanding the SMTP transaction can help diagnose if the rejection is content-related. If a rejection happens before the DATA command, the filter hasn't seen your email's content, pointing to issues with the sending IP, EHLO, or MAIL FROM address. If it occurs after DATA, the content itself is likely the culprit.

Klaviyo's logs might indicate where in the SMTP transaction the rejection happened, providing valuable clues.

Practical troubleshooting steps

Start by thoroughly examining your

Klaviyo bounce logs, specifically filtering for

Gmail addresses. While mailbox full messages are often temporary, it's essential to confirm if TempFail is tied to a suspected spam reason instead. This information is usually available in the JSON metadata associated with each bounced email. If

Klaviyo's interface doesn't provide enough detail, reaching out to their support team for deeper log analysis is a good next step, especially since they can access granular data for shared IP users. Also, review our article on troubleshooting delivery errors and TempFail messages for more specific help.

Utilize

Google Postmaster Tools (GPT) to monitor your sender reputation, spam rate, and delivery errors. While GPT doesn't identify specific IPs for shared sending, it can show trends in delivery issues. A discrepancy between low spam rates and high delivery errors, especially TempFail as suspected spam, indicates a filtering issue rather than recipient complaints. This could be due to a recent change in your email content, a specific segment of your list, or a transient issue affecting your shared IP. You can find more information about Google Postmaster Tools domain reputation in our in-depth guide.

If you use other email sending services or transactional email providers (e.g., AfterShip, Gorgias) alongside

Klaviyo, investigate their delivery logs for similar TempFail messages. It's possible the issue isn't exclusive to

Klaviyo but a broader domain reputation concern. Ensure all your sending domains are properly authenticated with SPF, DKIM, and DMARC, and that these records are aligned. An improperly configured DMARC, SPF, and DKIM setup can lead to delivery issues, even if your DMARC reports look healthy at a glance. Sometimes, even mailbox full errors can temporarily trigger reputation flags if they occur at scale.

Here's a comparison of initial troubleshooting steps in Klaviyo and Google Postmaster Tools:

Klaviyo Diagnostics

Bounce logs: Check the Klaviyo dashboard for delivery error reasons, focusing on Gmail addresses.
Recipient activity: Look for specific failed delivery reasons under the recipient's profile.
Campaign/flow performance: Identify if particular campaigns or flows have a higher rate of TempFail messages.

Google Postmaster Tools (GPT) Insights

Delivery errors dashboard: Monitor the chart for spikes, and click data points for TempFail reasons, such as suspected spam.
IP/Domain reputation: Check if your sender reputation is low, which can lead to higher TempFail rates.
Spam rate: Compare your spam rate with TempFail trends; low spam rates but high TempFail suggests filtering, not complaints.

Once you have identified a pattern, consider A/B testing your email content, subject lines, and sender names to see if changes impact the TempFail rate. Pay close attention to any links within your emails. If you use a custom link tracking domain or third-party services that add links, ensure these aren't on any blocklists (or blacklists). Sometimes, older, less reputable link shorteners can cause issues. If you suspect an issue with your shared IP in

Klaviyo, read our article on Klaviyo shared IP deliverability issues.

Maintaining strong sender reputation

Maintaining a strong sender reputation is paramount to avoiding delivery errors and TempFail messages. Even with high open rates, a significant volume of TempFail messages can indicate a reputation problem with

Gmail. Focus on consistent email volume, avoid sudden spikes, and segment your audience to send targeted content. Regularly clean your email lists to remove inactive or bouncing addresses, even those with mailbox full bounces, to signal good sending practices to ISPs. Our guide on fixing Gmail email deliverability issues offers more comprehensive solutions.

If TempFail messages persist, especially with a suspected spam reason, it often points to a domain reputation issue. Even if your

Gmail Postmaster Tools show good DMARC authentication, there might be other underlying factors contributing to a lower sender score. This includes content relevance, engagement rates, and even complaints that don't manifest as hard bounces. Continual monitoring and adaptation of your sending strategy are key to overcoming these challenges and improving overall email deliverability.

Key takeaways for resolving issues

Detailed log review: Always check Klaviyo bounce data and Google Postmaster Tools for specific TempFail reasons.
Content and links: Scrutinize email content and all links for anything that might trigger spam filters or appear on blocklists (or blacklists).
Sender reputation: Continuously work on improving your domain and IP reputation through good sending practices.
Audience segmentation: Target engaged segments to improve overall deliverability metrics.

Conclusion

Resolving delivery errors and TempFail messages in

Klaviyo when sending to

Gmail requires a systematic approach. By leveraging

Klaviyo's internal data and

Google Postmaster Tools, you can pinpoint the specific causes, whether it's content-related, reputation-based, or due to a temporary recipient issue. Consistent monitoring and adherence to email best practices will ensure your messages reliably reach the inbox.

Views from the trenches

Best practices

Actively monitor Klaviyo bounce logs and Google Postmaster Tools for specific error messages.

Segment your audience and tailor content to improve engagement and reduce negative signals.

Regularly clean your email lists to remove inactive subscribers and hard bounces.

Ensure all links in your emails are reputable and not on any blocklists (or blacklists).

Common pitfalls

Assuming high open rates mean perfect deliverability; TempFail messages can indicate hidden issues.

Ignoring mailbox full bounces, which can sometimes impact overall sender reputation.

Not differentiating between content-related and non-content-related rejections.

Overlooking third-party tools or secondary sending streams that might be causing problems.

Expert tips

If Gmail rejects before the DATA command, the issue is likely with your sender identity or IP, not content.

For shared IPs, work closely with Klaviyo support to understand specific log details.

A/B test your email content, including subject lines and calls to action, to see what performs best with Gmail filters.

Pay attention to the specific error codes in Postmaster Tools, they often provide actionable insights.

Expert view

Expert from Email Geeks says delivery errors are visible in your delivery logs, and you should filter for Google-specific errors (using `grep` for `gsmtp` if you have access) and follow the directions to address the issue.

2023-04-07 - Email Geeks

Marketer view

Marketer from Email Geeks says that you can check bounces for Gmail addresses in Klaviyo, and the reason will be in the metadata. In Google Postmaster Tools, clicking the dot on the graph might also provide insight into the reason, especially if it's a DMARC failure that's not clearly indicated in Klaviyo.

2023-04-07 - Email Geeks