How does Apple Relay affect email sender reputation and what causes suspected spam temp fails?

Summary

Apple Relay's direct impact on sender reputation is minimal due to message transformation, although it can indirectly skew open rates. Investigate temporary failures (temp fails) by checking logs and analyzing bounce codes; potential causes include greylisting, recipient server issues, spam filtering, network problems, and high email volume. While DKIM, SPF, and DMARC are important for authentication, they don't guarantee avoidance of spam filters. Focus on engagement metrics beyond open rates (CTR, conversions), maintain a clean email list, ensure relevant content, and actively monitor sender reputation using tools like Google Postmaster Tools and SendGrid. Properly configure email infrastructure and adhere to email best practices. Be aware of potential deliverability issues specific to Apple domains and the IP reputation of Apple's servers. If the temp fail happens after the DATA command in the SMTP transaction, it may be content-related.

Key findings

  • Apple Relay Impact: Apple Relay itself has minimal direct impact on reputation due to message transformation but it can indirectly impact open rates.
  • Temp Fail Causes: Temp fails arise from greylisting, server issues, spam filters, network problems, and high volume.
  • Authentication Limitations: DKIM, SPF, DMARC don't prevent spam classification; they are authentication methods.
  • Metrics Shift: Focus on CTR and conversions due to skewed open rates.
  • SMTP Timing: Content can cause a temp fail only if it happens after the DATA command.

Key considerations

  • Log Analysis: Check logs for deferred messages and reasons for temp fails.
  • Engagement Monitoring: Track CTR and conversions to understand campaign performance.
  • Reputation Tools: Actively use tools like Google Postmaster Tools and SendGrid's dashboard to monitor sender reputation.
  • Infrastructure Review: Ensure proper configuration of email infrastructure.
  • Content Scrutiny: If failures are content related - then review your email content and formatting.
  • Apple Specifics: Monitor deliverability to Apple domains and understand Apple IP reputation may play a factor

What email marketers say
9Marketer opinions

Apple Relay (Hide My Email) indirectly affects sender reputation by skewing open rates, making engagement assessment difficult. Temporary failures (temp fails) are caused by several factors: recipient server overloads, IP blacklisting, content triggering spam filters, and greylisting. Monitoring sender reputation via tools like Google Postmaster Tools and SendGrid is crucial. Focus on engagement metrics beyond open rates, like click-through rates and conversions, to accurately measure campaign performance. Ensuring a clean email list, relevant content, and proper authentication (SPF, DKIM, DMARC) are critical.

Key opinions

  • Apple Relay Impact: Apple Relay skews open rates, making engagement assessment difficult.
  • Temp Fail Causes: Temp fails result from server overloads, IP blacklisting, spam filters, and greylisting.
  • Monitoring Importance: Monitoring sender reputation is essential via tools like Google Postmaster Tools and SendGrid.
  • Alternative Metrics: Focus on click-through rates and conversions for accurate campaign performance insights.
  • Apple IP Effects: Problems with Apple's IP infrastructure could lead to deliverability challenges.

Key considerations

  • Data Skew Mitigation: Use engagement metrics beyond open rates to compensate for skewed data.
  • Infrastructure Monitoring: Continuously monitor server logs and SMTP error codes for bounce causes.
  • Reputation Health: Maintain a clean email list and relevant content for positive reputation.
  • Authentication: Utilize authentication methods like SPF, DKIM, and DMARC to help deliverability.
  • Apple Domain Issues: Monitor your campaigns for deliverability issues specific to Apple domains.
Marketer view

Email marketer from GlockApps notes that with Apple Relay, the IP reputation of Apple's servers can affect deliverability and suggests monitoring your campaigns for deliverability issues specific to Apple domains. Even if your own IP reputation is good, problems with Apple's infrastructure could lead to deliverability challenges.

June 2024 - GlockApps
Marketer view

Email marketer from Litmus suggests using a variety of engagement metrics beyond open rates to gauge campaign performance in light of Apple's MPP. They advise tracking click-through rates, website visits, and conversions to understand how recipients are truly interacting with your emails.

July 2021 - Litmus
Marketer view

Email marketer from Mailjet shares that temporary failures can be caused by a number of reasons, including server overload at the recipient, blacklisting of the sender IP, or content-related issues that trigger spam filters. Analyzing bounce codes can help identify the specific reason for the temp fail.

January 2025 - Mailjet
Marketer view

Email marketer from Reddit shares in a thread that Apple Relay can skew open rates, making it difficult to assess genuine engagement. They suggest focusing on click-through rates and conversion metrics to get a more accurate picture of campaign performance. They have also seen increased bounces from relay addresses.

January 2024 - Reddit
Marketer view

Email marketer from GMass explains that factors impacting sender reputation include spam complaints, bounce rates, and engagement metrics (opens, clicks). Maintaining a clean email list, sending relevant content, and authenticating emails (SPF, DKIM, DMARC) are crucial for maintaining a positive reputation.

October 2024 - GMass
Marketer view

Email marketer from Neil Patel Digital shares that Apple's Mail Privacy Protection (MPP), which includes Hide My Email (Apple Relay), can indirectly affect sender reputation. While it doesn't directly cause bounces, it can lead to inaccurate open rates, impacting how engaged your audience appears, which in turn can affect reputation with ISPs.

July 2022 - Neil Patel Digital
Marketer view

Email marketer from EmailOctopus explains that Apple's Hide My Email service can lead to deliverability challenges. While it protects user privacy, it can also obscure real engagement data, making it harder to optimize email campaigns and maintain a healthy sender reputation. They recommend focusing on other engagement metrics like click-through rates and conversions.

July 2021 - EmailOctopus
Marketer view

Email marketer from Email Geeks shares that to investigate tempfails you should check the logs to see how much mail was deferred and the message there and they likely accepted it eventually.

June 2024 - Email Geeks
Marketer view

Email marketer from SendGrid explains the importance of actively monitoring sender reputation using tools like Google Postmaster Tools and SendGrid's Reputation Dashboard. Monitoring helps identify potential issues, such as spam complaints or blacklisting, which can negatively impact deliverability.

July 2024 - SendGrid

What the experts say
5Expert opinions

Apple Relay generally doesn't impact sender reputation directly because Apple transforms and re-signs the messages. DKIM, SPF, and DMARC don't directly prevent spam classification. Temporary failures (temp fails) can stem from greylisting (temporary rejection), recipient server issues (overload, network problems), or suspicion of spam. The timing of the temp fail in the SMTP transaction (before or after DATA) indicates whether it's content-related.

Key opinions

  • Apple Relay Impact: Apple Relay has minimal direct impact on sender reputation due to message transformation.
  • Authentication vs. Spam: DKIM, SPF, and DMARC don't prevent messages from being marked as spam.
  • Temp Fail Causes: Temp fails are caused by greylisting, recipient server issues, or spam suspicion.
  • SMTP Timing: The timing of the temp fail within the SMTP transaction indicates whether the issue is content-related (after DATA).

Key considerations

  • Greylisting Awareness: Be aware that greylisting can cause temporary delivery delays and ensure your servers retry delivery.
  • Server Issue Diagnosis: Investigate recipient server issues (overload, network) when encountering temp fails.
  • Content Review: If temp fails occur after DATA, review email content and formatting for potential spam triggers.
  • Error Code Analysis: Analyze specific SMTP error codes to identify root causes of temporary bounces and delivery failures.
Expert view

Expert from Email Geeks answers that Apple Relay has almost no impact on sender reputation as Apple transforms the message, re-signs it, and changes the from address.

February 2022 - Email Geeks
Expert view

Expert from Spam Resource explains that temporary failures or temp fails can occur due to greylisting, a technique used by some mail servers to mitigate spam. Greylisting temporarily rejects emails from unknown senders, requiring the sending server to retry delivery. If the sending server is legitimate, it will retry, and the email will eventually be delivered. Illegitimate servers may not retry, thus reducing spam.

February 2024 - Spam Resource
Expert view

Expert from Email Geeks explains that DKIM, SPF, and DMARC have nothing to do with whether a message is marked as spam or not.

July 2023 - Email Geeks
Expert view

Expert from Email Geeks shares that if the temp fail happened before DATA in the SMTP transaction it's not content related but if it happened after DATA it may be content related.

December 2022 - Email Geeks
Expert view

Expert from Word to the Wise explains that temporary bounces can arise from various factors, including issues with the recipient's mail server (e.g., server overload), temporary network problems, or suspicion of spam. These are transient issues, and retrying the email delivery at a later time might be successful. Also lists a number of potential SMTP error codes that can be the cause.

May 2024 - Word to the Wise

What the documentation says
4Technical articles

Temporary failures (temp fails) are caused by greylisting, recipient server issues, suspected spam, network problems, and high email volume. High spam complaint rates negatively impact sender reputation, requiring explicit opt-ins and relevant content. SMTP servers use 4xx codes for transient delivery issues. Proper email infrastructure configuration and adherence to best practices are crucial to avoid spam flagging.

Key findings

  • Temp Fail Origins: Temp fails stem from greylisting, server issues, suspected spam, network problems, and high volume.
  • Spam Complaint Impact: High spam complaint rates significantly harm sender reputation.
  • SMTP Codes: SMTP servers use 4xx codes for temporary delivery failures.
  • Infrastructure & Best Practices: Proper configuration and adherence to best practices are essential to avoid spam flagging.

Key considerations

  • Monitor Failures: Actively monitor temp fails to identify patterns and address issues.
  • Opt-in Enforcement: Ensure explicit opt-ins and relevant content to minimize spam complaints.
  • Troubleshoot Network Issues: Investigate and resolve network and server-related delivery problems.
  • Review Infrastructure: Regularly review email infrastructure configuration and adherence to email best practices.
Technical article

Documentation from SparkPost explains that temporary failures (temp fails) can occur for various reasons, including greylisting (temporary rejection to combat spam), temporary server issues at the recipient's end, or suspected spam content. It is important to monitor these failures to identify patterns and address potential issues.

December 2021 - SparkPost
Technical article

Documentation from RFC 5321 explains that SMTP servers use temporary failure codes (4xx) to indicate that a message could not be delivered at the time but might be deliverable in the future. These failures can be due to temporary network issues, server overload, or other transient problems.

October 2021 - RFC Editor
Technical article

Documentation from Google Postmaster Tools explains that a high spam complaint rate significantly impacts sender reputation. Google actively monitors spam complaints and uses them to filter unwanted emails. Senders should aim for a low spam complaint rate by ensuring recipients have explicitly opted in to receive emails and that emails are relevant and valuable.

December 2022 - Google
Technical article

Documentation from Microsoft explains that email delays or failures (including temp fails) can be due to several reasons: server issues, network problems, high email volume, or spam filtering. Senders should ensure their email infrastructure is properly configured and that they adhere to email best practices to avoid being flagged as spam.

July 2021 - Microsoft