Summary
When Braze shows an email as delivered but it doesn't appear in the recipient's inbox, it indicates the message was accepted by the receiving mail server, but then it was filtered or routed elsewhere before reaching the user. This is a common deliverability challenge that can stem from various factors, including recipient-side filtering, authentication issues, or even temporary delays. Understanding Braze's definition of "delivered" is crucial here: it typically means the email was accepted by the recipient's server (a 250 OK response), not necessarily that it landed in the primary inbox or was seen by the user.
Key findings
- Server acceptance: Braze's "delivered" status confirms the receiving server accepted the email, usually via a 250 OK response. This acceptance doesn't guarantee inbox placement, only that the initial handoff was successful.
- Post-acceptance filtering: After acceptance, emails can be caught by spam filters, moved to junk or promotions folders, quarantined, or even silently dropped by the recipient's mail server or client-side rules. Learn more about why emails go missing or get silently dropped.
- Recipient-specific issues: If the issue is isolated to a single user, it often points to recipient-side factors like personal filters, a full inbox, or even the user accidentally moving the email.
- Authentication impact: Lack of proper email authentication (SPF, DKIM, DMARC) can lead to emails being filtered despite initial acceptance. Ensuring these are correctly configured is vital for deliverability.
Key considerations
- Investigate recipient side: Encourage the user to check their spam, junk, or promotions folders, as well as any custom filters or rules they might have set up. For corporate mail, ask about quarantine folders.
- Review Braze logs: While Braze shows "delivered," delve deeper into recipient-level details or event logs within the platform to see if there are any additional suppressed statuses or unique recipient behaviors. Braze's own documentation on email events might offer more context on temporary bounces or other post-delivery states.
- Check sender reputation: While unlikely for an isolated user, a decline in overall sender reputation (e.g., due to increased spam complaints) could lead to stricter filtering by ISPs like Gmail. For Gmail deliverability issues, regular monitoring is essential.
- Contact Braze support: Leverage Braze's deliverability team if the problem persists, as they have deeper insights into their logging and specific ISP relationships.
What email marketers say
Email marketers often face the perplexing issue of seeing emails marked as "delivered" in their platforms like Braze, yet not appearing in the recipient's inbox. Their experiences highlight that the problem often shifts from the sending platform's responsibility to the receiving server or even the individual recipient's email settings. The consensus among marketers points to post-acceptance filtering, user-side actions, or subtle ESP suppressions as primary culprits.
Key opinions
- Recipient-side filtering: Many marketers suspect that even after a successful delivery status, the email might be diverted by the recipient's personal filters, spam folders, or a corporate quarantine system (especially for business email).
- ESP suppression: Some marketers believe the email could be getting suppressed by the ESP itself, perhaps due to a previous complaint or an internal filtering mechanism, even if it initially shows as delivered.
- Gmail delays: While less common now, some marketers recall instances where Gmail (and other providers) would delay delivering mail to the inbox for a few hours, even if it was technically accepted. This is usually not a multi-day issue.
- User-level blocking: Marketers recognize that individual users might have blocked the sender, or inadvertently moved emails to archives or deleted them, leading to the perception of missing mail.
Key considerations
- Check user profile in ESP: Verify the user's interaction history and delivery status within Braze's user profile to see if there are any unusual patterns or specific suppression reasons. Although Braze shows it as delivered, there might be other signals.
- Confirm Braze's "delivered" definition: Understand that Braze's "delivered" status means the receiving server accepted the message. This doesn't mean it reached the inbox, only that it cleared the initial hurdle. This is explained in their email building documentation, where preview and test sends are common.
- Involve the user: Advise the recipient to add the sender to their address book, check their blocked list, and thoroughly inspect all email folders (spam, promotions, archives).
- Monitor deliverability overall: While an isolated issue, persistent deliverability problems can arise if emails are not appearing in the inbox more broadly. Regular checks and proactive measures are key.
Marketer view
Email marketer from Email Geeks notes the problem is usually caused by the user moving the email or by a rule that automatically moves it, emphasizing that this is a common symptom of a compromised account or misconfigured settings. This often falls outside the sending platform's immediate visibility after a successful handoff to the receiving server.
Marketer view
Marketer from Spiceworks Community suggests that if an email tracer shows 'delivered' but it's not in the inbox, it nearly always indicates the user either accidentally moved the email or a rule automatically moved it. This also commonly signals a compromised account.
What the experts say
Email deliverability experts agree that a "delivered" status from an ESP like Braze signifies successful handoff to the recipient's mail server, but not necessarily inbox arrival. The gap between server acceptance and inbox placement is where various anti-spam measures, user settings, and temporary issues come into play. Experts emphasize that the ultimate answer often lies with the recipient's mail provider (e.g., Gmail) and their internal filtering mechanisms, which are often opaque to senders.
Key opinions
- 250 OK response: Experts confirm that "delivered" means the sending ESP received a 250 OK SMTP response from the recipient's server, indicating acceptance for delivery. This is a crucial distinction from actual inbox placement.
- Anti-abuse filters: Post-acceptance, anti-abuse filters (spam, phishing, malware) on the receiving end often perform additional checks that can lead to messages being quarantined, moved to spam, or silently dropped. This is a common reason for emails going to spam.
- User-level factors: Individual user settings, such as personal blocklists, filtering rules, or even previous complaints, can cause emails to bypass the inbox. These are often the hardest to diagnose remotely.
- Lack of transparency: Only the recipient's email provider (e.g., Gmail) truly knows the final disposition of an email after acceptance. This lack of transparency is a significant challenge in deliverability troubleshooting.
Key considerations
- Examine headers and logs: If possible, request the full email headers from the recipient. These can sometimes reveal the path an email took after leaving Braze and identify any filtering actions. For insights into common issues, consider our guide on Microsoft Outlook and Hotmail deliverability.
- Email authentication review: Ensure your SPF, DKIM, and DMARC records are correctly configured and aligned. A common reason for filtering is poor authentication, even if the email is initially accepted. Check out a simple guide to DMARC, SPF, and DKIM.
- Sender reputation monitoring: Continuously monitor your sender reputation using tools like Google Postmaster Tools. A poor reputation can lead to inboxing issues. This is a critical factor addressed by deliverability experts in addressing Microsoft domain fixes.
- Contact recipient ISP: While challenging, if the issue is widespread for a specific domain, contacting the recipient's postmaster can sometimes yield insights, especially for large corporate domains.
Expert view
Expert from Email Geeks advises asking Braze for their precise definition of "delivered" and whether they received a 250 OK SMTP response. If so, the user should then check their filters and spam folders, or consult any additional anti-abuse filters that might have accepted but not deposited the message.
Expert view
Expert from Spamresource, an industry blog, emphasizes that a 'delivered' status means the recipient server accepted the email. Subsequent filtering into spam or junk folders, or even silent drops, are common actions taken by the recipient's mail system based on reputation or content.
What the documentation says
Technical documentation from various sources clarifies the nuances of email delivery status, particularly the distinction between a message being "accepted by the server" and its actual arrival in a user's inbox. This gap is often where automated spam filters, internal routing rules, or temporary network conditions intercept messages. Documentation emphasizes that the sending platform's role often ends once the receiving server provides an initial acceptance signal (e.g., 250 OK).
Key findings
- Server acceptance vs. inbox: Documentation confirms that "delivered" means the email was accepted by the recipient's mail server. It explicitly does not guarantee the message was delivered to a device or landed in the primary inbox.
- Post-acceptance processes: Many mail servers perform additional checks after initial acceptance, including anti-spam filtering, virus scans, and content analysis, which can prevent emails from reaching the inbox.
- Temporary bounces/delays: Temporary reasons like a full inbox or a down email server can cause a soft bounce, which some systems might interpret differently or handle with delayed retries. Braze's technical documentation for event streams confirms such scenarios.
- User-configured rules: User-defined rules within their email client can automatically move emails to other folders, making them seem "missing" despite successful delivery to the mailbox.
Key considerations
- Review ESP event logs: Consult event logs or detailed delivery reports within your ESP (e.g., Braze Currents) for more granular information on what happened after the initial server acceptance. This can reveal soft bounces or other specific statuses.
- Adhere to best practices: Even after delivery, adherence to email best practices, including proper authentication (SPF, DKIM, DMARC) and low spam complaint rates, is critical for consistent inbox placement. Neglecting these can lead to broader deliverability issues.
- Understand ISP filtering: Recognize that major ISPs (Internet Service Providers) like Gmail have sophisticated internal filters that operate beyond the initial SMTP acceptance. Their filtering decisions are complex and proprietary, as noted by security and email filtering documentation.
- Test and preview: Use your ESP's preview and test send functions, sometimes with randomly selected users, to identify if specific email attributes or content trigger filtering before a full send.
Technical article
Documentation from RudderStack, concerning Braze, indicates that a "bounced" event is triggered when Braze attempts to send an email but the recipient's email server temporarily rejects it due to reasons such as a full inbox or the email server being down. This shows nuances even within server acceptance, as a temporary bounce might not always be immediately flagged as undelivered by all systems.
Technical article
Documentation from SAP Community states that in most cases where logs show an email was delivered but not in the mailbox, it happens when a mail server accepts the email, but then anti-spam filters perform additional checks. This situation is most commonly caused by content or sender reputation issues.
Related resources
9 resources
Related pages
Why are emails not appearing in the inbox despite ESP reporting successful delivery?
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