--- title: "Microsoft’s 000 Reason for Email Failure With DMARC | DuoCircle" description: "Microsoft’s 000 Reason for Email Failure With DMARC." image: "https://www.duocircle.com/images/og-default.png" canonical: "https://www.duocircle.com/blog/dmarc/microsofts-000-reason-for-email-failure-with-dmarc/" --- Quick Answer When Outlook recipients receive your mail in spam with header line dmarc=fail action=oreject ... reason=000, SPF and/or DKIM passed but DMARC alignment failed under Microsoft's interpretation. The cause is usually strict alignment (aspf=s) combined with a Return-Path on a subdomain like pm-bounces.yourdomain.com while the From is yourdomain.com. With aspf=r (relaxed), that subdomain alignment passes; with aspf=s, it fails. Microsoft does not reject DMARC failures outright (to avoid false positives from forwarders and stale lists); instead it routes them to spam, hence the 000 code. Fixes: switch SPF alignment to relaxed unless you have a hard reason for strict, use the same organizational domain for Return-Path and From, maintain a current safe-sender list, or create a Microsoft 365 Transport rule that quarantines unauthorized inbound. Validate SPF, DKIM, and DMARC records with lookup tools before publishing changes. Microsoft’s 000 Reason for Email Failure With DMARC Your browser does not support the audio element. [ Download episode](https://media.mailhop.org/duocircle/images/2024/03/Microsofts-000-Reason-for-Email-Failure-With-DMARC.mp3) Share [ ](https://www.linkedin.com/sharing/share-offsite/?url=undefined%2Fblog%2Fdmarc%2Fmicrosofts-000-reason-for-email-failure-with-dmarc%2F "Share on LinkedIn") [ ](https://twitter.com/intent/tweet?text=Microsoft%E2%80%99s%20000%20Reason%20for%20Email%20Failure%20With%20DMARC&url=undefined%2Fblog%2Fdmarc%2Fmicrosofts-000-reason-for-email-failure-with-dmarc%2F "Share on X/Twitter") [ ](https://www.facebook.com/sharer/sharer.php?u=undefined%2Fblog%2Fdmarc%2Fmicrosofts-000-reason-for-email-failure-with-dmarc%2F "Share on Facebook") [ ](https://reddit.com/submit?url=undefined%2Fblog%2Fdmarc%2Fmicrosofts-000-reason-for-email-failure-with-dmarc%2F&title=Microsoft%E2%80%99s%20000%20Reason%20for%20Email%20Failure%20With%20DMARC "Share on Reddit") [ ](mailto:?subject=Microsoft%E2%80%99s%20000%20Reason%20for%20Email%20Failure%20With%20DMARC&body=Check out this article: undefined%2Fblog%2Fdmarc%2Fmicrosofts-000-reason-for-email-failure-with-dmarc%2F "Share via Email") ![Email Failure With DMARC](https://media.mailhop.org/duocircle/images/2024/03/spf-validator-7145.jpg) If you notice outgoing emails going to spam folders of only [Outlook](/email-security/microsoft-email-attacks-an-inside-look-at-the-outlook-breach/) recipients and reflecting a **‘000’ reason**, then it means your messages failed [DMARC](/email/dmarc) with ‘quarantine’ or ‘reject’ effects. You are likely to see the following snippet from the [headers of email](/email-services/learning-to-trace-back-emails-to-their-source-ip-addresses/) messages getting dumped in the spam folders- `_Authentication-Results: spf=pass (sender IP is 106.225.909.126) smtp.mailfrom=pm-bounces.yourdomain.com; dkim=pass (signature was verified) header.d=pm.mtasv.net;dmarc=fail action=oreject header.from=domain.com;compauth=fail reason=000_` ## What Does This Mean? _As per Microsoft, emails that failed and reflected a [‘000’ reason](https://learn.microsoft.com/en-us/microsoft-365/security/office-365-security/message-headers-eop-mdo?view=o365-worldwide) are the ones whose SPF and/or DKIM checks pass but DMARC fails._ _You can choose to set one of the two [DMARC alignment](/dmarc/dmarc-relaxed-vs-strict-alignment/) modes in your DMARC records for SPF and DKIM- Relaxed mode (represented by ‘r’) OR Strict mode (represented by ‘s’)._ The relaxed alignment mode means that the [Return-Path](https://bird.com/guides/return-path-explained) domain can be a subdomain of the From address. Whereas, on the other hand, strict alignment mode implies that the Return-Path domain should be **exactly the same** as the domain in the From address. Let’s say your [DMARC record](/content/spf-record-check/dmarc-record-check) is set to **aspf=r**; in that case, the following should be a pass- From: manager Return-Path: [pm\_bounces@pm-bounces.yourdomain.com](mailto:pm%5Fbounces@pm-bounces.yourdomain.com) Since the Return-Path domain ‘pm-bounces.yourdomain.com” is a **subdomain** of “yourdomain.com,” the result would be considered a pass. However, if your DMARC record is set to **aspf=s**, this would be **reflected as a fail** as the Return-Path domain and subdomain are not exactly the same. [![DMARC policies](https://media.mailhop.org/duocircle/images/2024/03/email-smtp-service.jpg)](https://media.mailhop.org/duocircle/images/2024/03/email-smtp-service.jpg) As per DMARC specifications, either [SPF](/content/spf-record-check) or DKIM should align and pass for DMARC to pass and emails to land in the [primary inboxes](https://mailmeteor.com/glossary/primary-folder) of the desired recipients. _However, Microsoft happens to use a different method when it comes to **strict alignment with SPF**_. Please note that this situation may only impact you if you have a [DMARC policy](/resources/dmarc-policy) that allows you to [quarantine or reject](https://dmarc.org/overview/). ## Additional Information Microsoft refrains from rejecting emails as it takes the occurrences of [false positives](https://www.nospamproxy.de/en/what-is-a-false-positive-and-what-is-a-false-negative/) that may result from [email forwarding](/email/email-forwarding) or using outdated email lists into account. This also prevents legitimate email conversations from getting hampered due to **configuration issues** on the sender’s end. Thus, it’s suggested that you create an **updated** and [safe sender list](https://publiqsoftware.com/2022/01/did-you-know-safe-sender-list/). Alternatively, you can also create a [Microsoft 365 Transport rule](https://exclaimer.com/email-signature-handbook/office-365-transport-rules/) to quarantine **unauthorized inbound emails**. This can be done in two ways. If mail is received by internal domains in the “From” address, you can establish and configure a transport rule to mark the emails as spam. This will place the email into the **user’s spam folder** instead of their primary inbox. However, if you receive emails from domains falling outside the scope of your organization (external domains) that fail DMARC, you can set up a disclaimer, alerting users of a possible [phishing attack](https://www.digitalinformationworld.com/2024/03/business-email-compromise-attacks-are.html) or any other [malicious activity](https://www.scmagazine.com/news/subdomailing-manipulates-subdomains-to-send-spam-malicious-emails). [![DMARC reports](https://media.mailhop.org/duocircle/images/2024/03/spf-permerror-9716.jpg)](https://media.mailhop.org/duocircle/images/2024/03/spf-permerror-9716.jpg) At [DuoCircle](/), we suggest using SPF, [DKIM](/resources/what-is-dkim), and DMARC lookup tools to keep your records **non-erroneous** and opting for receiving [DMARC reports](/resources/dmarc-aggregate-report) to get insights into your domain’s email activities. ## Topics DMARCemail securityTrends ![Brad Slavin](https://media.mailhop.org/dmarcreport/images/team/brad-slavin.jpg) Brad Slavin General Manager General Manager at DuoCircle. Product strategy and commercial lead across the email security portfolio. ## Secure your email infrastructure Protect, authenticate, and deliver. Contact our team to find the right solution. [Contact Sales](/contact/) [Explore Products](/products/) ## Related Articles [ DMARC 6m Causes and Solutions of DMARC Failures Apr 2, 2024 ](/blog/dmarc/causes-and-solutions-of-dmarc-failures/)[ DMARC 3m DMARC For Shopify Users Mar 14, 2024 ](/blog/dmarc/dmarc-for-shopify-users/)[ DMARC 4m External Domain Verification for DMARC Reporting and Monitoring Jan 24, 2024 ](/blog/dmarc/external-domain-verification-for-dmarc-reporting-and-monitoring/)[ DMARC 8m How Does DMARC Help Marketers Improving Email Deliverability? Apr 24, 2024 ](/blog/dmarc/how-does-dmarc-help-marketers-improving-email-deliverability/) ```json {"@context":"https://schema.org","@type":"Organization","name":"DuoCircle LLC","url":"https://www.duocircle.com","logo":{"@type":"ImageObject","url":"https://www.duocircle.com/images/duocircle-logo.png"},"description":"DuoCircle is a portfolio of specialized email products covering protection, authentication, delivery, and routing. We deliver about 90% of category-leader capability at roughly half the price, backed by experts who own the outcome. Trusted by 50,000+ organizations since 2014.","subOrganization":[{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138898167","name":"DMARC Report","url":"https://dmarcreport.com"},{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138897474","name":"AutoSPF","url":"https://autospf.com"},{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138897912","name":"Phish Protection","url":"https://www.phishprotection.com"}],"sameAs":["https://www.linkedin.com/company/duocircle","https://x.com/duocirclellc","https://www.facebook.com/duocirclellc","https://www.g2.com/products/phish-protection-by-duocircle/reviews","https://github.com/duocircle","https://www.crunchbase.com/organization/duocircle-llc"],"contactPoint":{"@type":"ContactPoint","contactType":"customer support","url":"https://support.duocircle.com"},"knowsAbout":["Email Security","Email Authentication","SPF","DKIM","DMARC","Phishing Protection","Spam Filtering","SMTP Relay","Email Deliverability","Email Forwarding"]} ``` ```json {"@context":"https://schema.org","@type":"WebSite","name":"DuoCircle LLC","url":"https://www.duocircle.com","description":"DuoCircle is a portfolio of specialized email products covering protection, authentication, delivery, and routing. We deliver about 90% of category-leader capability at roughly half the price, backed by experts who own the outcome. Trusted by 50,000+ organizations since 2014.","publisher":{"@type":"Organization","name":"DuoCircle LLC","url":"https://www.duocircle.com","logo":{"@type":"ImageObject","url":"https://www.duocircle.com/images/duocircle-logo.png"},"description":"DuoCircle is a portfolio of specialized email products covering protection, authentication, delivery, and routing. We deliver about 90% of category-leader capability at roughly half the price, backed by experts who own the outcome. Trusted by 50,000+ organizations since 2014.","subOrganization":[{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138898167","name":"DMARC Report","url":"https://dmarcreport.com"},{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138897474","name":"AutoSPF","url":"https://autospf.com"},{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138897912","name":"Phish Protection","url":"https://www.phishprotection.com"}]}} ``` ```json [{"@context":"https://schema.org","@type":"BlogPosting","headline":"Microsoft’s 000 Reason for Email Failure With DMARC","description":"Microsoft’s 000 Reason for Email Failure With DMARC.","url":"https://www.duocircle.com/blog/dmarc/microsofts-000-reason-for-email-failure-with-dmarc/","datePublished":"2024-03-05T14:46:32.000Z","dateModified":"2025-05-23T13:49:12.000Z","dateCreated":"2024-03-05T14:46:32.000Z","author":{"@type":"Person","@id":"https://www.duocircle.com/authors/brad-slavin/#person","name":"Brad Slavin","url":"https://www.duocircle.com/authors/brad-slavin/","jobTitle":"General Manager","description":"Brad Slavin runs DuoCircle, the company behind DMARC Report, AutoSPF, Phish Protection, and Mailhop. His focus is product strategy, customer relationships, and the commercial and compliance side of email authentication (DPAs, SLAs, enterprise procurement).","image":"https://media.mailhop.org/dmarcreport/images/team/brad-slavin.jpg","knowsAbout":["Email Security Strategy","SaaS Product Management","Enterprise Compliance","Customer Success","Email Deliverability Business"],"worksFor":{"@type":"Organization","name":"DuoCircle LLC","url":"https://www.duocircle.com"},"sameAs":["https://www.linkedin.com/in/bradslavin"]},"publisher":{"@type":"Organization","name":"DuoCircle LLC","url":"https://www.duocircle.com","logo":{"@type":"ImageObject","url":"https://www.duocircle.com/images/duocircle-logo.png"},"description":"DuoCircle is a portfolio of specialized email products covering protection, authentication, delivery, and routing. We deliver about 90% of category-leader capability at roughly half the price, backed by experts who own the outcome. Trusted by 50,000+ organizations since 2014.","subOrganization":[{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138898167","name":"DMARC Report","url":"https://dmarcreport.com"},{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138897474","name":"AutoSPF","url":"https://autospf.com"},{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138897912","name":"Phish Protection","url":"https://www.phishprotection.com"}]},"mainEntityOfPage":{"@type":"WebPage","@id":"https://www.duocircle.com/blog/dmarc/microsofts-000-reason-for-email-failure-with-dmarc/"},"articleSection":"dmarc","keywords":"DMARC, email security, Trends","wordCount":495,"image":{"@type":"ImageObject","url":"https://media.mailhop.org/duocircle/images/2024/03/spf-validator-7145.jpg","caption":"Email Failure With DMARC","width":900,"height":600},"speakable":{"@type":"SpeakableSpecification","cssSelector":[".answer-block","h1"]}},{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Blog","item":"https://www.duocircle.com/blog/"},{"@type":"ListItem","position":2,"name":"DMARC"},{"@type":"ListItem","position":3,"name":"Microsoft’s 000 Reason for Email Failure With DMARC","item":"https://www.duocircle.com/blog/dmarc/microsofts-000-reason-for-email-failure-with-dmarc/"}]}] ``` ```json {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://www.duocircle.com/"},{"@type":"ListItem","position":2,"name":"Blog","item":"https://www.duocircle.com/blog/"},{"@type":"ListItem","position":3,"name":"DMARC","item":"https://www.duocircle.comundefined"},{"@type":"ListItem","position":4,"name":"Microsoft’s 000 Reason for Email Failure With DMARC","item":"https://www.duocircle.com/blog/dmarc/microsofts-000-reason-for-email-failure-with-dmarc/"}]} ``` ```json {"@context":"https://schema.org","@type":"BlogPosting","headline":"Microsoft’s 000 Reason for Email Failure With DMARC","description":"Microsoft’s 000 Reason for Email Failure With DMARC.","url":"https://www.duocircle.com/blog/dmarc/microsofts-000-reason-for-email-failure-with-dmarc/","datePublished":"2024-03-05T14:46:32.000Z","dateModified":"2025-05-23T13:49:12.000Z","dateCreated":"2024-03-05T14:46:32.000Z","author":{"@type":"Person","@id":"https://www.duocircle.com/authors/brad-slavin/#person","name":"Brad Slavin","url":"https://www.duocircle.com/authors/brad-slavin/","jobTitle":"General Manager","description":"Brad Slavin runs DuoCircle, the company behind DMARC Report, AutoSPF, Phish Protection, and Mailhop. His focus is product strategy, customer relationships, and the commercial and compliance side of email authentication (DPAs, SLAs, enterprise procurement).","image":"https://media.mailhop.org/dmarcreport/images/team/brad-slavin.jpg","knowsAbout":["Email Security Strategy","SaaS Product Management","Enterprise Compliance","Customer Success","Email Deliverability Business"],"worksFor":{"@type":"Organization","name":"DuoCircle LLC","url":"https://www.duocircle.com"},"sameAs":["https://www.linkedin.com/in/bradslavin"]},"publisher":{"@type":"Organization","name":"DuoCircle LLC","url":"https://www.duocircle.com","logo":{"@type":"ImageObject","url":"https://www.duocircle.com/images/duocircle-logo.png"},"description":"DuoCircle is a portfolio of specialized email products covering protection, authentication, delivery, and routing. We deliver about 90% of category-leader capability at roughly half the price, backed by experts who own the outcome. Trusted by 50,000+ organizations since 2014.","subOrganization":[{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138898167","name":"DMARC Report","url":"https://dmarcreport.com"},{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138897474","name":"AutoSPF","url":"https://autospf.com"},{"@type":"Organization","@id":"https://www.wikidata.org/wiki/Q138897912","name":"Phish Protection","url":"https://www.phishprotection.com"}]},"mainEntityOfPage":{"@type":"WebPage","@id":"https://www.duocircle.com/blog/dmarc/microsofts-000-reason-for-email-failure-with-dmarc/"},"articleSection":"dmarc","keywords":"DMARC, email security, Trends","wordCount":495,"image":{"@type":"ImageObject","url":"https://media.mailhop.org/duocircle/images/2024/03/spf-validator-7145.jpg","caption":"Email Failure With DMARC","width":900,"height":600},"speakable":{"@type":"SpeakableSpecification","cssSelector":[".answer-block","h1"]}} ```