What does the Braze error code soft bounce mean, specifically 'unable to get mx info: failed to get IPs from PTR record'?
Michael Ko
Co-founder & CEO, Suped
Published 19 May 2025
Updated 19 Aug 2025
8 min read
Encountering email bounce errors can be frustrating, especially when they come with cryptic messages. If you are using Braze and see a soft bounce with the specific message 'unable to get mx info: failed to get IPs from PTR record: lookup : unrecognized address', it indicates a particular type of delivery challenge.
This error means that the mail server attempting to deliver your message could not properly identify the recipient's mail server. It points to a fundamental issue with the domain's DNS records, specifically involving MX (Mail Exchange) records. While it’s labeled a soft bounce, which implies a temporary issue, the underlying problem can sometimes persist if not addressed.
Decoding the Braze error message
Understanding what each part of the error message signifies is crucial for effective troubleshooting. The core of the problem lies in the sending server's inability to resolve the recipient domain's mail exchange information.
The role of MX records
MX records are a type of DNS record that specifies which mail servers accept incoming mail for a domain and where email messages should be routed. When an email is sent, the sending mail server performs a DNS query to find the MX record for the recipient's domain. If this lookup fails, or if the MX record points to a non-existent or misconfigured server, the email cannot be delivered.
The PTR record confusion
The mention of 'failed to get IPs from PTR record' can be a bit misleading. PTR records (Pointer Records) are used for reverse DNS lookups, mapping an IP address back to a domain name. While important for email authentication and reputation, they are not typically used to find the initial MX information or the IPs of an MX server. This part of the error might indicate a broader issue with DNS resolution or a specific diagnostic quirk of the sending system, such as what SendGrid indicates for this type of problem. It often boils down to the fact that the recipient domain is simply not configured correctly for email reception.
Essentially, the sending server, when trying to deliver the email, encounters a domain that, for all intents and purposes, doesn't seem to have a valid destination for mail according to its DNS records. This is why it's categorized as a soft bounce, as the system attempts to deliver but is temporarily blocked by this DNS resolution issue.
Why it's a soft bounce (and why it matters)
A soft bounce means the email address itself is valid, but the email couldn't be delivered for a temporary reason. This contrasts with a hard bounce, which indicates a permanent delivery failure to an invalid address. Understanding this distinction is key to managing your email lists and maintaining good sender reputation. For more on this, you can read our guide on why you might be getting soft bounces.
The 'unable to get mx info' error, while a soft bounce, points to a structural issue with the recipient domain's mail configuration. It's not about a full mailbox or a temporary server overload, but rather the sending server's inability to even find where to send the email.
Potential underlying causes
One common cause is a newly set up domain whose DNS records, especially MX records, have not yet propagated or were configured incorrectly. Another could be a legitimate domain that is experiencing temporary DNS server issues or has recently migrated its email services. In some cases, it might also indicate a domain that simply doesn't exist anymore or has removed its email capabilities without proper redirection.
While the system tries again later, repeated failures will still count as a soft bounce. If the issue persists, these addresses behave more like hard bounces because they never successfully receive mail. For more details on this, you can refer to the RFC 5321 specification regarding mail exchange and fallback mechanisms.
Troubleshooting steps for senders
Addressing this particular soft bounce requires focusing on the recipient's DNS setup. Here are some steps you can take from your end to diagnose and potentially mitigate the issue:
Investigate recipient domain's DNS
Check MX records: Use a DNS lookup tool to verify the MX records for the problematic domain. If there are no MX records, or they point to an invalid host, that's your primary clue. Sometimes, a no MX bounce reason will be reported directly, but this Braze error can also cover that scenario.
Verify PTR records (if applicable): While less directly related to finding the MX, issues with PTR records (as mentioned in the error) can sometimes point to broader DNS problems for the recipient's infrastructure. You can learn more about PTR record issues and how they affect bounces.
Clean your email list
This error can often indicate a 'bad' domain or an email address that is no longer valid, even if it's technically a soft bounce. Regularly cleaning your email list to remove addresses that consistently soft bounce is a crucial best practice. This helps improve your overall email deliverability rates and prevents your sending IP from getting a bad reputation or being added to a blocklist (or blacklist).
Engage with recipients
If these bounces are happening for a significant number of recipients at a particular domain, it may be worth reaching out to the IT or email administrator of that organization. They might be unaware of their DNS configuration issues. This is especially relevant for transactional emails where deliverability is critical.
Preventative measures and long-term strategy
Proactive monitoring of your email deliverability metrics and bounce logs is paramount. Waiting until you see a high volume of these specific soft bounces means you've already experienced delivery failures.
Leverage reporting tools
Braze, like other email service providers, provides detailed bounce reporting. Regularly review these logs, not just for the 'unable to get mx info' error, but for all bounce reasons. Identifying patterns can help pinpoint systemic issues, whether they relate to specific domains or overall list hygiene.
Maintain a healthy sender reputation
Even soft bounces can impact your sender reputation over time, especially if they are numerous and persistent. A high bounce rate, even soft bounces, signals to ISPs that your list quality may be poor, potentially leading to your emails being routed to spam folders or even your IP address (or domain) being added to a blocklist (or blacklist). Make sure your email authentication records, like DMARC, SPF, and DKIM, are correctly configured to bolster your reputation.
A good sender reputation is your best defense against delivery issues, including those caused by recipient-side DNS problems. It ensures that when a temporary issue occurs, your emails are more likely to be deferred and retried, rather than immediately rejected or sent to spam.
Views from the trenches
Views from the trenches
Best practices
Always validate email addresses at the point of collection to prevent adding malformed or non-existent domains to your list.
Regularly review your Braze message activity logs to catch specific bounce reasons like 'unable to get mx info' early.
Segment your list based on bounce types and frequency to identify persistently problematic domains.
Common pitfalls
Ignoring soft bounces, as recurring soft bounces can degrade your sender reputation over time, acting like hard bounces.
Not understanding the underlying DNS components (MX, PTR records) contributing to these specific errors.
Failing to clean your list of consistently bouncing addresses, which can lead to higher bounce rates.
Expert tips
Use a DNS lookup tool to manually verify MX records for domains causing these errors.
Be aware that the 'PTR record' mention might be a byproduct of a broader DNS lookup failure, rather than a direct PTR issue.
Prioritize list hygiene; a clean list minimizes the chances of hitting domains with bad DNS configurations.
Marketer view
A marketer from Email Geeks says they saw a huge number of soft bounces, nearly five million for 81,000 unique users, which looked like Braze was counting each deferral.
2022-01-01 - Email Geeks
Marketer view
A marketer from Email Geeks says they would be more concerned about the addresses without MX records, suggesting an issue with the opt-in process allowing fake addresses.
2022-01-01 - Email Geeks
Key takeaways for email deliverability
While the Braze soft bounce 'unable to get mx info: failed to get IPs from PTR record' might seem complex, it primarily signals a problem with the recipient domain's MX records or overall DNS configuration. By understanding that this is a temporary delivery deferral, you can focus your efforts on identifying problematic domains and maintaining a healthy email list.
Proactive list cleaning, consistent monitoring of bounce reasons, and ensuring your own sender reputation is strong are your best tools for minimizing the impact of such errors. Ultimately, these steps contribute to better inbox placement and more effective email campaigns.
