{"id":5309,"date":"2026-03-20T03:43:54","date_gmt":"2026-03-20T03:43:54","guid":{"rendered":"https:\/\/emailwarmup.com\/blog\/?p=5309"},"modified":"2026-03-20T03:43:55","modified_gmt":"2026-03-20T03:43:55","slug":"how-to-fix-535-5-7-3-authentication-unsuccessful-office-365-oauth","status":"publish","type":"post","link":"https:\/\/emailwarmup.com\/blog\/email-errors\/how-to-fix-535-5-7-3-authentication-unsuccessful-office-365-oauth\/","title":{"rendered":"How To Fix 535 5.7.3 | Authentication Unsuccessful (Office 365\/OAuth)"},"content":{"rendered":"\n<figure class=\"wp-block-image size-full\"><img fetchpriority=\"high\" decoding=\"async\" width=\"3196\" height=\"2034\" src=\"https:\/\/emailwarmup.com\/blog\/wp-content\/uploads\/2026\/03\/535-5.7.3.jpg\" alt=\"535 5.7.3\" class=\"wp-image-5310\"\/><\/figure>\n\n\n\n<p>The 535 5.7.3 error means Microsoft 365 rejected your SMTP authentication \u2014 typically because <em>Authenticated SMTP<\/em> is disabled for the user, Security Defaults are blocking legacy auth, or OAuth2 configuration is incorrect.&nbsp;<\/p>\n\n\n\n<p>Fix it by enabling Authenticated SMTP in the Microsoft 365 Admin Center, disabling Security Defaults (if legacy auth is required), and verifying OAuth2 scopes for https:\/\/outlook.office365.com\/.default.<\/p>\n\n\n\n<p>Microsoft has progressively tightened authentication requirements. Basic SMTP auth works only when explicitly enabled per-user, and modern security policies often block it entirely.&nbsp;<\/p>\n\n\n\n<p>Moreover, if you&#8217;re developing applications, OAuth2 is the recommended (and increasingly <em>required<\/em>) authentication method for Microsoft 365 SMTP.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Quick skim \u2014 535 5.7.3 error overview<\/h2>\n\n\n\n<p>The 535 5.7.3 error indicates Microsoft-specific SMTP authentication failure.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td>Attribute<\/td><td>Details<\/td><\/tr><tr><td>Error code<\/td><td>535 5.7.3<\/td><\/tr><tr><td>Category<\/td><td>Microsoft 365 authentication<\/td><\/tr><tr><td>Meaning<\/td><td>SMTP authentication unsuccessful<\/td><\/tr><tr><td>Severity<\/td><td>Permanent (requires admin configuration)<\/td><\/tr><tr><td>Common causes<\/td><td>SMTP auth disabled, Security Defaults, OAuth misconfiguration<\/td><\/tr><tr><td>Fix approach<\/td><td>Enable SMTP auth \u2192 check Security Defaults \u2192 verify OAuth2<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">What does authentication unsuccessful mean?<\/h2>\n\n\n\n<p>Microsoft 365 restricts SMTP authentication to prevent credential-based attacks. By default, users <em>cannot<\/em> authenticate via basic SMTP \u2014 the feature must be explicitly enabled. Additionally, tenant-wide security policies may block legacy authentication methods entirely.&nbsp;<\/p>\n\n\n\n<p>The authentication hierarchy looks like:<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td>Policy Level<\/td><td>What It Controls<\/td><\/tr><tr><td>Per-user SMTP<\/td><td>Whether a specific user can authenticate via SMTP<\/td><\/tr><tr><td>Security Defaults<\/td><td>Tenant-wide legacy auth blocking<\/td><\/tr><tr><td>Conditional Access<\/td><td>Policy-based authentication restrictions<\/td><\/tr><tr><td>MFA requirements<\/td><td>Multi-factor authentication enforcement<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p>The 535 5.7.3 error appears when any level blocks your authentication attempt.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Why does the 535 5.7.3 error occur?<\/h2>\n\n\n\n<p>Multiple Microsoft 365 settings can prevent SMTP authentication.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Authenticated SMTP disabled<\/h3>\n\n\n\n<p>The most common cause \u2014 SMTP auth isn&#8217;t enabled for the user:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The default setting is <em>disabled<\/em> for all users<\/li>\n\n\n\n<li>Must be explicitly enabled per-user<\/li>\n\n\n\n<li>Admin action required<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Security Defaults enabled<\/h3>\n\n\n\n<p>Tenant-wide Security Defaults block legacy authentication:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Automatically enabled on newer tenants<\/li>\n\n\n\n<li>Blocks basic SMTP authentication<\/li>\n\n\n\n<li>Requires modern auth (OAuth2) or explicit disable<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Per-user MFA conflict<\/h3>\n\n\n\n<p>Legacy multi-factor authentication can interfere:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Per-user MFA (older style) blocks some auth methods<\/li>\n\n\n\n<li>Conditional Access MFA handles authentication better<\/li>\n\n\n\n<li>Mixed MFA approaches cause conflicts<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">OAuth2 misconfiguration<\/h3>\n\n\n\n<p>For applications using OAuth2:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Wrong scope specified<\/li>\n\n\n\n<li>Access token expired<\/li>\n\n\n\n<li>Incorrect SMTP server address<\/li>\n\n\n\n<li>Missing API permissions<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">How do you fix 535 5.7.3?<\/h2>\n\n\n\n<p>Start with the most common fix (enabling SMTP auth), then address policy conflicts.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Enable Authenticated SMTP<\/h3>\n\n\n\n<p>Turn on SMTP for the specific user:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Go to Microsoft 365 Admin Center<\/li>\n\n\n\n<li>Navigate to Users \u2192 Active users<\/li>\n\n\n\n<li>Select the affected user<\/li>\n\n\n\n<li>Click Mail \u2192 Manage email apps<\/li>\n\n\n\n<li>Check <em>Authenticated SMTP<\/em><\/li>\n\n\n\n<li>Save changes<\/li>\n<\/ul>\n\n\n\n<p>Changes typically apply within 15-30 minutes (sometimes faster).<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Toggle SMTP setting<\/h3>\n\n\n\n<p>If already enabled but not working:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Uncheck Authenticated SMTP<\/li>\n\n\n\n<li>Save changes<\/li>\n\n\n\n<li>Wait 5 minutes<\/li>\n\n\n\n<li>Re-check Authenticated SMTP<\/li>\n\n\n\n<li>Save again<\/li>\n<\/ul>\n\n\n\n<p>The toggle-reset sometimes clears stuck states (a frustrating but effective workaround).<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Disable Security Defaults<\/h3>\n\n\n\n<p>If your tenant uses Security Defaults and you need basic SMTP:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Go to Microsoft Entra ID (Azure AD)<\/li>\n\n\n\n<li>Navigate to Properties<\/li>\n\n\n\n<li>Manage Security Defaults<\/li>\n\n\n\n<li>Set to <em>No<\/em> (disabled)<\/li>\n<\/ul>\n\n\n\n<p>Disabling Security Defaults removes tenant-wide legacy auth blocking. However, this reduces security \u2014 consider Conditional Access policies for granular control instead.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Disable per-user MFA<\/h3>\n\n\n\n<p>Legacy per-user MFA can conflict with SMTP:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Go to Microsoft 365 Admin Center<\/li>\n\n\n\n<li>Navigate to Users \u2192 Active users<\/li>\n\n\n\n<li>Click Multi-factor authentication<\/li>\n\n\n\n<li>Select the user<\/li>\n\n\n\n<li>Disable per-user MFA<\/li>\n<\/ul>\n\n\n\n<p>Use Conditional Access MFA instead for better compatibility with various authentication methods.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Configure OAuth2 correctly<\/h3>\n\n\n\n<p>For applications using OAuth2:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Use server: smtp.office365.com<\/li>\n\n\n\n<li>Use port: 587<\/li>\n\n\n\n<li>Enable TLS\/STARTTLS<\/li>\n\n\n\n<li>Scope: https:\/\/outlook.office365.com\/.default<\/li>\n\n\n\n<li>Ensure the app has SMTP.Send permission in Azure AD<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Refresh access tokens<\/h3>\n\n\n\n<p>OAuth2 tokens expire:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Access tokens typically last 1 hour<\/li>\n\n\n\n<li>Implement token refresh logic<\/li>\n\n\n\n<li>Don&#8217;t cache expired tokens<\/li>\n\n\n\n<li>Handle refresh failures gracefully<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Check Conditional Access<\/h3>\n\n\n\n<p>If Conditional Access policies exist:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Review policies affecting the user<\/li>\n\n\n\n<li>Check for blocks on legacy authentication<\/li>\n\n\n\n<li>Verify SMTP isn&#8217;t explicitly blocked<\/li>\n\n\n\n<li>Consider policy exceptions for specific apps<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">How do you prevent authentication failures?<\/h2>\n\n\n\n<p>Proper planning prevents recurring 535 5.7.3 errors.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Plan the authentication method<\/h3>\n\n\n\n<p>Choose your approach before implementation:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Basic SMTP auth (requires per-user enablement, blocked by some policies)<\/li>\n\n\n\n<li>OAuth2 (recommended for applications, more complex setup)<\/li>\n\n\n\n<li>SMTP relay (for devices that can&#8217;t authenticate)<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Document configurations<\/h3>\n\n\n\n<p>Track what&#8217;s enabled for whom:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Which users have SMTP auth enabled<\/li>\n\n\n\n<li>What policies affect authentication<\/li>\n\n\n\n<li>OAuth2 app registrations and permissions<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Monitor authentication health<\/h3>\n\n\n\n<p>Set up alerts for authentication failures:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Track SMTP auth failures in Azure AD logs<\/li>\n\n\n\n<li>Monitor for policy changes affecting auth<\/li>\n\n\n\n<li>Review sign-in logs for blocked attempts<\/li>\n<\/ul>\n\n\n\n\n<!-- EmailWarmup \u2014 Email Errors Campaign CTA Section -->\n<section id=\"ew-email-errors-consult\" aria-label=\"Help fixing email errors\">\n  <style>\n    \/* Scoped, theme-safe resets *\/\n    #ew-email-errors-consult, #ew-email-errors-consult *{\n      box-sizing:border-box;\n      -webkit-hyphens:none!important; 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Others point to deeper deliverability issues involving authentication, sender reputation, blacklisting, routing, or mailbox provider policy. If you would rather have an expert review it, speak with an\n      <a href=\"https:\/\/emailwarmup.com\/email-deliverability-consultant\">email delieverability consultant<\/a>\n      for free and we can help diagnose the issue and fix it on your behalf.\n    <\/p>\n  <\/div>\n\n  <div class=\"tiles\" role=\"list\">\n    <article class=\"tile t1\" role=\"listitem\">\n      <div class=\"icon\" aria-hidden=\"true\">\n        <svg width=\"18\" height=\"18\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\">\n          <path d=\"M21 15a2 2 0 0 1-2 2H7l-4 4V5a2 2 0 0 1 2-2h14a2 2 0 0 1 2 2z\"><\/path>\n        <\/svg>\n      <\/div>\n      <div>\n        <span class=\"h3like\">Root cause analysis<\/span>\n        <p>We look beyond the error message itself to find what is actually breaking delivery, trust, or inbox placement.<\/p>\n      <\/div>\n    <\/article>\n\n    <article class=\"tile t2\" role=\"listitem\">\n      <div class=\"icon\" aria-hidden=\"true\">\n        <svg width=\"18\" height=\"18\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\">\n          <path d=\"M20 6L9 17l-5-5\"><\/path>\n        <\/svg>\n      <\/div>\n      <div>\n        <span class=\"h3like\">Technical fixes handled for you<\/span>\n        <p>From SPF, DKIM, and DMARC to blacklist cleanup, DNS alignment, and sending setup, we can guide or implement the fix.<\/p>\n      <\/div>\n    <\/article>\n\n    <article class=\"tile t3\" role=\"listitem\">\n      <div class=\"icon\" aria-hidden=\"true\">\n        <svg width=\"18\" height=\"18\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\">\n          <path d=\"M12 20V10\"><\/path>\n          <path d=\"M18 20V4\"><\/path>\n          <path d=\"M6 20v-4\"><\/path>\n        <\/svg>\n      <\/div>\n      <div>\n        <span class=\"h3like\">Deliverability-first review<\/span>\n        <p>We assess whether the error is part of a bigger pattern hurting opens, replies, and overall campaign performance.<\/p>\n      <\/div>\n    <\/article>\n\n    <article class=\"tile t4\" role=\"listitem\">\n      <div class=\"icon\" aria-hidden=\"true\">\n        <svg width=\"18\" height=\"18\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\">\n          <path d=\"M12 12c2.8 0 5-2.2 5-5s-2.2-5-5-5-5 2.2-5 5 2.2 5 5 5z\"><\/path>\n          <path d=\"M2 22c1.5-4 5.5-6 10-6s8.5 2 10 6\"><\/path>\n        <\/svg>\n      <\/div>\n      <div>\n        <span class=\"h3like\">Free expert consultation<\/span>\n        <p>Talk to a real deliverability expert, get honest guidance, and see the next best step without pressure or upsells.<\/p>\n      <\/div>\n    <\/article>\n  <\/div>\n\n  <div class=\"bottom\">\n    <p>\n      <strong>When should you book a consultation?<\/strong> If the error keeps coming back, affects multiple mailboxes or domains, started after an ESP or DNS change, or is tied to spam placement, low inboxing, high bounce rates, or authentication failures, it is usually faster to get an expert involved early.\n    <\/p>\n  <\/div>\n\n  <div class=\"cta\">\n    <a class=\"btn\" href=\"https:\/\/emailwarmup.com\/email-deliverability-consultant\" target=\"_blank\" rel=\"noopener\">\n      Talk to a deliverability expert for free\n      <svg width=\"18\" height=\"18\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\" aria-hidden=\"true\">\n        <path d=\"M5 12h14\"><\/path>\n        <path d=\"M12 5l7 7-7 7\"><\/path>\n      <\/svg>\n    <\/a>\n  <\/div>\n<\/section>\n\n\n\n\n\n<h2 class=\"wp-block-heading\">Frequently asked questions<\/h2>\n\n\n\n<p>Here are some commonly asked questions about this error:<\/p>\n\n\n\n<div class=\"schema-faq wp-block-yoast-faq-block\"><div class=\"schema-faq-section\" id=\"faq-question-1773976747897\"><strong class=\"schema-faq-question\">Why is SMTP auth disabled by default?<\/strong> <p class=\"schema-faq-answer\">Microsoft disabled basic SMTP authentication by default to reduce the risk of credential-based attacks. Basic auth transmits passwords (potentially exposing them to interception), while modern auth (OAuth2) uses tokens that expire and can be revoked. Microsoft&#8217;s security posture prioritizes modern authentication.<\/p> <\/div> <div class=\"schema-faq-section\" id=\"faq-question-1773976752970\"><strong class=\"schema-faq-question\">Can I use basic SMTP with Security Defaults enabled?<\/strong> <p class=\"schema-faq-answer\">No. Security Defaults blocks all legacy authentication methods, including basic SMTP. You must either disable Security Defaults (reducing security) or implement Conditional Access policies that allow specific legacy auth scenarios while blocking others.<\/p> <\/div> <div class=\"schema-faq-section\" id=\"faq-question-1773976761273\"><strong class=\"schema-faq-question\">Should I use OAuth2 or basic auth?<\/strong> <p class=\"schema-faq-answer\">OAuth2 is recommended (and increasingly required) for applications. Basic auth is acceptable for personal email clients where OAuth2 isn&#8217;t supported. For programmatic sending, always prefer OAuth2 \u2014 it&#8217;s more secure and won&#8217;t break when Microsoft further restricts basic auth.<\/p> <\/div> <\/div>\n","protected":false},"excerpt":{"rendered":"<p>The 535 5.7.3 error means Microsoft 365 rejected your SMTP authentication \u2014 typically because Authenticated SMTP is disabled for the user, Security Defaults are blocking legacy auth, or OAuth2 configuration is incorrect.&nbsp; Fix it by enabling Authenticated SMTP in the Microsoft 365 Admin Center, disabling Security Defaults (if legacy auth is required), and verifying OAuth2 [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":5310,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_uag_custom_page_level_css":"","footnotes":""},"categories":[38],"tags":[],"class_list":["post-5309","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-email-errors"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v25.0 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>How To Fix 535 5.7.3 | Authentication Unsuccessful<\/title>\n<meta name=\"description\" content=\"The 535 5.7.3 error means Microsoft 365 rejected your SMTP authentication \u2014 typically. Let&#039;s learn how to fix it.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/emailwarmup.com\/blog\/email-errors\/how-to-fix-535-5-7-3-authentication-unsuccessful-office-365-oauth\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"How To Fix 535 5.7.3 | Authentication Unsuccessful\" \/>\n<meta property=\"og:description\" content=\"The 535 5.7.3 error means Microsoft 365 rejected your SMTP authentication \u2014 typically. 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For programmatic sending, always prefer OAuth2 \u2014 it's more secure and won't break when Microsoft further restricts basic auth.","inLanguage":"en-US"},"inLanguage":"en-US"}]}},"uagb_featured_image_src":{"full":["https:\/\/emailwarmup.com\/blog\/wp-content\/uploads\/2026\/03\/535-5.7.3.jpg",3196,2034,false],"thumbnail":["https:\/\/emailwarmup.com\/blog\/wp-content\/uploads\/2026\/03\/535-5.7.3.jpg",150,95,false],"medium":["https:\/\/emailwarmup.com\/blog\/wp-content\/uploads\/2026\/03\/535-5.7.3.jpg",300,191,false],"medium_large":["https:\/\/emailwarmup.com\/blog\/wp-content\/uploads\/2026\/03\/535-5.7.3.jpg",768,489,false],"large":["https:\/\/emailwarmup.com\/blog\/wp-content\/uploads\/2026\/03\/535-5.7.3.jpg",1024,652,false],"1536x1536":["https:\/\/emailwarmup.com\/blog\/wp-content\/uploads\/2026\/03\/535-5.7.3.jpg",1536,978,false],"2048x2048":["https:\/\/emailwarmup.com\/blog\/wp-content\/uploads\/2026\/03\/535-5.7.3.jpg",2048,1303,false],"profile_24":["https:\/\/emailwarmup.com\/blog\/wp-content\/uploads\/2026\/03\/535-5.7.3.jpg",24,15,false],"profile_48":["https:\/\/emailwarmup.com\/blog\/wp-content\/uploads\/2026\/03\/535-5.7.3.jpg",48,31,false],"profile_96":["https:\/\/emailwarmup.com\/blog\/wp-content\/uploads\/2026\/03\/535-5.7.3.jpg",96,61,false],"profile_150":["https:\/\/emailwarmup.com\/blog\/wp-content\/uploads\/2026\/03\/535-5.7.3.jpg",150,95,false],"profile_300":["https:\/\/emailwarmup.com\/blog\/wp-content\/uploads\/2026\/03\/535-5.7.3.jpg",300,191,false]},"uagb_author_info":{"display_name":"Daniyal Dehleh","author_link":"https:\/\/emailwarmup.com\/blog\/author\/daniyaldehleh\/"},"uagb_comment_info":0,"uagb_excerpt":"The 535 5.7.3 error means Microsoft 365 rejected your SMTP authentication \u2014 typically because Authenticated SMTP is disabled for the user, Security Defaults are blocking legacy auth, or OAuth2 configuration is incorrect.&nbsp; Fix it by enabling Authenticated SMTP in the Microsoft 365 Admin Center, disabling Security Defaults (if legacy auth is required), and verifying OAuth2&hellip;","_links":{"self":[{"href":"https:\/\/emailwarmup.com\/blog\/wp-json\/wp\/v2\/posts\/5309","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/emailwarmup.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/emailwarmup.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/emailwarmup.com\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/emailwarmup.com\/blog\/wp-json\/wp\/v2\/comments?post=5309"}],"version-history":[{"count":1,"href":"https:\/\/emailwarmup.com\/blog\/wp-json\/wp\/v2\/posts\/5309\/revisions"}],"predecessor-version":[{"id":5311,"href":"https:\/\/emailwarmup.com\/blog\/wp-json\/wp\/v2\/posts\/5309\/revisions\/5311"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/emailwarmup.com\/blog\/wp-json\/wp\/v2\/media\/5310"}],"wp:attachment":[{"href":"https:\/\/emailwarmup.com\/blog\/wp-json\/wp\/v2\/media?parent=5309"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/emailwarmup.com\/blog\/wp-json\/wp\/v2\/categories?post=5309"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/emailwarmup.com\/blog\/wp-json\/wp\/v2\/tags?post=5309"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}