How do I troubleshoot and fix SPF and DMARC settings for email deliverability issues?

Email marketer from AuthSMTP explains that having multiple SPF records can invalidate SPF authentication. You should consolidate all SPF records into a single record.

Email marketer from Mailjet shares that DMARC implementation should be done in stages: starting with a 'p=none' policy to monitor reports, then moving to 'p=quarantine' and finally 'p=reject' as you gain confidence in your authentication setup.

Marketer from Email Geeks suggests not worrying about MXToolbox warnings. They agree with removing the `mx` from the SPF record to reduce DNS overhead and note that Sendgrid's SPF domain is typically something like `foo456789.example.com`, which is where the SPF should be, not the organizational domain. They also mention that Mailchimp now provides 2 DKIM public TXT/CNAME records instead of requiring an SPF include.

Marketer from Email Geeks advises that Sendgrid implementation under the root domain's SPF record should be reviewed and that Mailchimp's include isn't needed because they use their own Return-Path for bounce handling. They suggest tracking DMARC aggregate reports and achieving full authentication for every outgoing mail stream.

Email marketer from Postmark shares that using subdomains for sending different types of emails (e.g., transactional vs. marketing) can help isolate deliverability issues and simplify SPF and DMARC management.

Email marketer from Email on Acid shares the importance of using email testing tools to validate SPF and DMARC configurations. Send test emails and analyze the headers to ensure proper authentication.

Email marketer from Reddit suggests that SPF failures can occur due to email forwarding, so consider implementing Sender Rewriting Scheme (SRS) to rewrite the sender address and maintain SPF validation.

Email marketer from an Email Marketing Forum says that continuous testing and monitoring are critical. Use tools to check SPF and DMARC records and actively monitor deliverability rates to identify and address issues promptly.

Marketers from Email Geeks discuss DMARC monitoring and reject modes. They agree monitoring mode is useful for fixing authentication issues, but 'p=reject' isn't for everyone and should be treated as an ongoing project. Hagop emphasizes value of DMARC vendors and their alerts/reports, while Neil mentions the risk with only DKIM aligned and DKIM breaks causing DMARC failures. They agree domain owners should implement DMARC with reporting-only for the benefits.

Marketer from Email Geeks suggests that if a DMARC deployment is promised in less than 6 months or costs less than $20,000, it's likely not a genuine service. They also suspect the client may only need an SPF record update rather than a full DMARC deployment.

Marketers from Email Geeks clarifies that Mailchimp has moved away from needing the 'include' in the SPF record. Hagop K. explains new users get 2 DKIM TXT/CNAME records, while Neil agrees this reduces overhead for Mailchimp but prefers custom domain authentication options. Hagop K. highlights that DMARC needs either SPF or DKIM pass, so lack of custom return-path setup isn't a killer, as DKIM should suffice.

Email marketer from EasyDMARC explains common SPF mistakes such as exceeding the 10 DNS lookup limit or having multiple SPF records, and advises to flatten SPF records to reduce lookups and consolidate them into a single record.

Email marketer from Stack Overflow says that to fix DMARC validation failures, ensure that either SPF or DKIM is aligned with the 'From:' domain. If SPF fails, DKIM must pass and be aligned. Check your DKIM signature and DNS records.

Email marketer from MXToolbox explains that common SPF record syntax errors, like typos, missing includes, or incorrect mechanisms, can cause authentication failures. Use an SPF record checker to identify and correct these errors.

Marketer from Email Geeks identifies a valid SPF TXT record for the domain and suggests removing the 'mx' mechanism as it is covered by the Microsoft include, which could tidy it up.

Expert from Spam Resource explains that when troubleshooting DMARC, start with a policy of 'p=none' to monitor traffic and identify legitimate sending sources before gradually increasing the policy to 'p=quarantine' or 'p=reject.' This approach minimizes the risk of blocking legitimate emails and allows for thorough testing.

Expert from Email Geeks explains there's nothing to 'fix' if DMARC record isn't published and multiple SPF records are bad, the correct ones depend on where mail is sent from.

Expert from Email Geeks generally recommends using one of the actual DMARC companies for DMARC setup, as they possess a suite of tools that makes the process easier compared to general consultants.

Expert from Email Geeks confirms seeing situations with only DKIM alignment where mail fails a DMARC check, citing Microsoft issues. Hagop lists scenarios like incorrect DKIM record, unreachable DNS, short DKIM key, or message modifications. Hagop adds DMARC enforcement can be tricky for domains with complex infrastructures and advises being cautious with providers lacking DKIM authentication, and mentions ARC specifications will work better with indirect mail flows as policy is enforced.

Expert from Word to the Wise responds that a common issue with SPF records is exceeding the 10 DNS lookup limit, which can cause SPF failures. To fix this, flatten your SPF record by replacing 'include:' mechanisms with the actual IP addresses of the sending servers. This reduces the number of DNS lookups required and ensures SPF validation.

Documentation from Valimail explains that DMARC failure reports can highlight specific authentication issues such as SPF softfails or DKIM signature problems. Understanding these reports requires analyzing the XML data for clues about the reasons for failure.

Documentation from Microsoft shares a guide on identifying if SPF or DMARC are causing email delivery issues, suggesting reviewing the message headers for authentication results and verifying the DNS records are correctly configured.

Documentation from RFC Editor shares that regularly monitoring DMARC aggregate and forensic reports is crucial for identifying authentication issues, potential abuse, and misconfigured sending sources. Analyzing these reports helps refine your SPF and DMARC policies.

Documentation from Google explains that to fix SPF setup issues, ensure the SPF record is correctly formatted, published at the root domain, includes all sending sources, and doesn't exceed the 10 DNS lookup limit.

Documentation from DMARC.org highlights common DMARC errors including syntax errors in the DMARC record, incorrect policy application, and failure to monitor DMARC reports. Correcting these involves fixing the record, applying the correct policy, and regularly monitoring reports.