{"id":34355,"date":"2026-02-06T13:00:25","date_gmt":"2026-02-06T13:00:25","guid":{"rendered":"https:\/\/1grid.co.za\/knowledge\/?post_type=ht_kb&#038;p=34355"},"modified":"2026-02-06T13:00:29","modified_gmt":"2026-02-06T13:00:29","slug":"understanding-smtp-ports-and-ssl-tls-encryption","status":"publish","type":"ht_kb","link":"https:\/\/1grid.co.za\/knowledge\/understanding-smtp-ports-and-ssltls-encryption\/","title":{"rendered":"Understanding SMTP Ports and SSL\/TLS Encryption"},"content":{"rendered":"\n<p>If\u00a0you\u2019ve\u00a0ever seen errors like \u201cCannot connect to SMTP server\u201d or \u201cEncryption mismatch\u201d,\u00a0the issue is usually not your mailbox;\u00a0it\u2019s\u00a0the port or security setting.\u00a0Understanding SMTP ports and SSL\/TLS encryption helps determine what might be causing sending issues with your emails.\u00a0<\/p>\n\n\n\n<p>This guide will help you understand SMTP ports, SSL\/TLS encryption, and how they work together to keep your email sending reliable and secure.\u00a0<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"1600\" height=\"600\" src=\"https:\/\/1grid.co.za\/knowledge\/wp-content\/uploads\/2026\/02\/1-grid-Images-for-KB-Articles-1000-x-600-px-56.png\" alt=\"SMTP Ports and SSL-TLS Encryption\" class=\"wp-image-34358\"\/><\/figure>\n<\/div>\n\n\n<div class=\"wp-block-ht-block-toc  is-style-outline htoc htoc--position-wide toc-list-style-plain\" data-htoc-state=\"expanded\"><span class=\"htoc__title\"><span class=\"ht_toc_title\">Table of Contents<\/span><span class=\"htoc__toggle\"><svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"16\" height=\"16\"><g fill=\"#444\"><path d=\"M15 7H1c-.6 0-1 .4-1 1s.4 1 1 1h14c.6 0 1-.4 1-1s-.4-1-1-1z\"><\/path><path d=\"M15 1H1c-.6 0-1 .4-1 1s.4 1 1 1h14c.6 0 1-.4 1-1s-.4-1-1-1zM15 13H1c-.6 0-1 .4-1 1s.4 1 1 1h14c.6 0 1-.4 1-1s-.4-1-1-1z\"><\/path><\/g><\/svg><\/span><\/span><div class=\"htoc__itemswrap\"><ul class=\"ht_toc_list\"><li class=\"\"><a href=\"#htoc-at-a-glance\">At a Glance&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-what-is-smtp\">What Is SMTP?&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-what-are-smtp-ports\">What Are SMTP Ports?&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-key-smtp-ports-explained-simply\">Key SMTP Ports (Explained Simply)&nbsp;<\/a><ul class=\"ht_toc_child_list\"><li class=\"\"><a href=\"#htoc-port-587-recommended\">Port 587&nbsp;(Recommended)&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-port-465-secure-smtps\">Port 465&nbsp;(Secure SMTPS)&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-port-25-legacy-server-to-server\">Port 25&nbsp;(Legacy \/ Server-to-Server)&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-port-2525-alternative-option\">Port 2525&nbsp;(Alternative Option)&nbsp;<\/a><\/li><\/ul><\/li><li class=\"\"><a href=\"#htoc-understanding-ssl-vs-tls-encryption\">Understanding SSL vs TLS Encryption&nbsp;<\/a><ul class=\"ht_toc_child_list\"><li class=\"\"><a href=\"#htoc-what-they-do\">What They Do&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-ssl-vs-tls\">SSL vs TLS&nbsp;<\/a><\/li><\/ul><\/li><li class=\"\"><a href=\"#htoc-how-encryption-works-high-level\">How Encryption Works (High Level)&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-how-to-configure-smtp-general-steps\">How to Configure SMTP (General Steps)&nbsp;<\/a><ul class=\"ht_toc_child_list\"><\/ul><\/li><li class=\"\"><a href=\"#htoc-common-smtp-issues-and-fast-fixes\">Common SMTP Issues (And Fast Fixes)&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-best-practices-email-stability\">Best Practices (Email Stability)&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-our-scope-of-support\">Our&nbsp;Scope of Support&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-faqs\">FAQs&nbsp;<\/a><\/li><li class=\"\"><a href=\"#htoc-additional-resources\">Additional&nbsp;Resources&nbsp;<\/a><\/li><\/ul><\/div><\/div>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-at-a-glance\"><strong>At a Glance<\/strong>&nbsp;<\/h2>\n\n\n\n<p>Choosing&nbsp;the right port once&nbsp;avoids&nbsp;repeated send failures.&nbsp;<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td><strong>Port<\/strong>&nbsp;<\/td><td><strong>Best Used For<\/strong>&nbsp;<\/td><td><strong>Security<\/strong>&nbsp;<\/td><\/tr><tr><td>587&nbsp;<\/td><td>Mail clients (recommended)\u00a0<\/td><td>TLS via STARTTLS&nbsp;<\/td><\/tr><tr><td>465&nbsp;<\/td><td>Secure legacy setups&nbsp;<\/td><td>Implicit SSL\/TLS&nbsp;<\/td><\/tr><tr><td>25&nbsp;<\/td><td>Server-to-server relay&nbsp;<\/td><td>Usually blocked&nbsp;<\/td><\/tr><tr><td>2525&nbsp;<\/td><td>Alternative fallback&nbsp;<\/td><td>TLS supported&nbsp;<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-what-is-smtp\"><strong>What Is SMTP?<\/strong>&nbsp;<\/h2>\n\n\n\n<p>SMTP is for sending\u00a0emails, not receiving them.\u00a0<\/p>\n\n\n\n<p><strong>SMTP (Simple Mail Transfer Protocol)<\/strong>&nbsp;is the system that&nbsp;<strong>sends emails from your device, mail&nbsp;client&nbsp;or application to the recipient\u2019s mail server<\/strong>.&nbsp;<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-used-for-outgoing-mail-only\">Used for\u00a0<strong>outgoing mail only<\/strong>\u00a0<\/li>\n\n\n\n<li id=\"htoc-works-with-email-clients-like-outlook-thunderbird-mobile-apps-and-websites\">Works with email clients like Outlook, Thunderbird, mobile apps, and websites\u00a0<\/li>\n\n\n\n<li id=\"htoc-receiving-mail-uses-imap-or-pop3-not-smtp\">Receiving mail uses\u00a0<a href=\"https:\/\/1grid.co.za\/knowledge\/what-is-the-difference-between-imap-and-pop\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>IMAP or POP3<\/strong><\/a>, not SMTP\u00a0<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-what-are-smtp-ports\"><strong>What Are SMTP Ports?<\/strong>&nbsp;<\/h2>\n\n\n\n<p>SMTP ports are&nbsp;<strong>connection channels<\/strong>&nbsp;used by your email client to communicate with the mail server.&nbsp;<\/p>\n\n\n\n<p>Each port:&nbsp;<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-serves-a-specific-purpose\">Serves a\u00a0<strong>specific purpose<\/strong>\u00a0<\/li>\n\n\n\n<li id=\"htoc-supports-different-security-methods\">Supports\u00a0<strong>different security methods<\/strong>\u00a0<\/li>\n\n\n\n<li id=\"htoc-may-be-blocked-by-isps-or-networks\">May be\u00a0<strong>blocked by ISPs or networks<\/strong>\u00a0<\/li>\n<\/ul>\n\n\n\n<p>Choosing the wrong one often causes&nbsp;<strong>send failures<\/strong>, even when login details are correct.&nbsp;<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-key-smtp-ports-explained-simply\"><strong>Key SMTP Ports (Explained Simply)<\/strong>&nbsp;<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"htoc-port-587-recommended\"><strong>Port 587&nbsp;(<\/strong><strong>Recommended<\/strong><strong><em>)<\/em><\/strong>&nbsp;<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-modern-standard-for-email-submission\">Modern standard for email submission\u00a0<\/li>\n\n\n\n<li id=\"htoc-requires-authentication\">Requires authentication\u00a0<\/li>\n\n\n\n<li id=\"htoc-uses-starttls-to-upgrade-to-a-secure-connection\">Uses\u00a0<strong>STARTTLS<\/strong>\u00a0to upgrade to a secure connection\u00a0<\/li>\n\n\n\n<li id=\"htoc-best-compatibility-with-isps-and-firewalls\">Best compatibility with ISPs and firewalls\u00a0<\/li>\n<\/ul>\n\n\n\n<p><strong>Use this port unless&nbsp;told otherwise.<\/strong>&nbsp;<\/p>\n\n\n\n<p><strong>TIP:\u00a0<\/strong>If the email\u00a0won\u2019t\u00a0send, switch to port 587 with STARTTLS.\u00a0<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"htoc-port-465-secure-smtps\"><strong>Port 465&nbsp;(Secure SMTPS)<\/strong>&nbsp;<\/h3>\n\n\n\n<p>Encryption starts&nbsp;immediately&nbsp;on connection.&nbsp;<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-uses-implicit-ssl-tls\">Uses\u00a0<strong>implicit SSL\/TLS<\/strong>\u00a0<\/li>\n\n\n\n<li id=\"htoc-entire-session-is-encrypted-from-the-start\">Entire session is encrypted from the start\u00a0<\/li>\n\n\n\n<li id=\"htoc-still-supported-by-many-providers\">Still supported by many providers\u00a0<\/li>\n\n\n\n<li id=\"htoc-useful-for-older-systems-or-specific-apps\">Useful for older systems or specific apps\u00a0<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"htoc-port-25-legacy-server-to-server\"><strong>Port 25&nbsp;(Legacy \/ Server-to-Server)<\/strong>&nbsp;<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-historically-used-for-mail-relay\">Historically used for mail relay\u00a0<\/li>\n\n\n\n<li id=\"htoc-typically-unencrypted\">Typically\u00a0unencrypted\u00a0<\/li>\n\n\n\n<li id=\"htoc-commonly-blocked-by-isps-to-prevent-spam\">Commonly blocked by ISPs to prevent spam\u00a0<\/li>\n\n\n\n<li id=\"htoc-best-reserved-for-mail-servers-only\">Best reserved for\u00a0<strong>mail servers only<\/strong>\u00a0<\/li>\n<\/ul>\n\n\n\n<p><strong>IMPORTANT:&nbsp;<\/strong>This port is often blocked, so it is not recommended for email clients.&nbsp;<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"htoc-port-2525-alternative-option\"><strong>Port 2525&nbsp;(Alternative Option)<\/strong>&nbsp;<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-not-officially-standard\">Not officially standard\u00a0<\/li>\n\n\n\n<li id=\"htoc-commonly-used-as-a-backup-submission-port\">Commonly used as a\u00a0<strong>backup submission port<\/strong>\u00a0<\/li>\n\n\n\n<li id=\"htoc-supports-tls-encryption\">Supports TLS encryption\u00a0<\/li>\n\n\n\n<li id=\"htoc-useful-on-restricted-networks\">Useful on restricted networks\u00a0<\/li>\n<\/ul>\n\n\n\n<p><strong>TIP:&nbsp;<\/strong>Try this if 587 is blocked by a network.&nbsp;<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-understanding-ssl-vs-tls-encryption\"><strong>Understanding SSL vs TLS Encryption<\/strong>&nbsp;<\/h2>\n\n\n\n<p>\u201cSSL\u201d usually means TLS.&nbsp;<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"htoc-what-they-do\"><strong>What They Do<\/strong>&nbsp;<\/h3>\n\n\n\n<p>Encryption protects email&nbsp;<strong>in transit<\/strong>, preventing:&nbsp;<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-eavesdropping\"><a href=\"https:\/\/www.proofpoint.com\/au\/threat-reference\/eavesdropping\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Eavesdropping<\/strong><\/a>\u00a0<\/li>\n\n\n\n<li id=\"htoc-data-tampering\"><a href=\"https:\/\/www.tributech.io\/blog\/cybersecurity-threat-data-tampering\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Data tampering<\/strong><\/a>\u00a0<\/li>\n\n\n\n<li id=\"htoc-credential-theft\"><a href=\"https:\/\/www.crowdstrike.com\/en-us\/cybersecurity-101\/cyberattacks\/credential-theft\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Credential theft<\/strong><\/a>\u00a0<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"htoc-ssl-vs-tls\"><strong>SSL vs TLS<\/strong>&nbsp;<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-ssl-deprecated-but-still-used-as-a-name\"><strong>SSL<\/strong>: Deprecated, but still used as a name\u00a0<\/li>\n\n\n\n<li id=\"htoc-tls-modern-secure-standard\"><strong>TLS<\/strong>: Modern, secure standard\u00a0<\/li>\n\n\n\n<li id=\"htoc-starttls-upgrades-an-insecure-connection-to-tls-commonly-on-port-587\"><strong>STARTTLS<\/strong>: Upgrades an insecure connection to TLS (commonly on port 587)\u00a0<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-how-encryption-works-high-level\"><strong>How Encryption Works (High Level)<\/strong>&nbsp;<\/h2>\n\n\n\n<p>Encryption happens&nbsp;automatically,&nbsp;so&nbsp;no action&nbsp;is&nbsp;required.&nbsp;<\/p>\n\n\n\n<ol start=\"1\" class=\"wp-block-list\">\n<li id=\"htoc-the-client-and-server-agree-on-encryption\">The client and server agree on encryption\u00a0<\/li>\n\n\n\n<li id=\"htoc-the-server-presents-a-certificate\">The server presents a certificate\u00a0<\/li>\n\n\n\n<li id=\"htoc-the-secure-session-keys-are-created\">The secure session keys are created\u00a0<\/li>\n\n\n\n<li id=\"htoc-the-email-is-transmitted-securely\">The email is transmitted securely\u00a0<\/li>\n<\/ol>\n\n\n\n<ol start=\"2\" class=\"wp-block-list\"><\/ol>\n\n\n\n<ol start=\"3\" class=\"wp-block-list\"><\/ol>\n\n\n\n<ol start=\"4\" class=\"wp-block-list\"><\/ol>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-how-to-configure-smtp-general-steps\"><strong>How to Configure SMTP (General Steps)<\/strong>&nbsp;<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"htoc-quick-setup-checklist\"><strong>Quick Setup&nbsp;Checklist:<\/strong>&nbsp;<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-outgoing-server-mail-yourdomain\">Outgoing server:\u00a0mail.yourdomain\u00a0<\/li>\n\n\n\n<li id=\"htoc-port-587\">Port:\u00a0<strong>587<\/strong>\u00a0<\/li>\n\n\n\n<li id=\"htoc-encryption-starttls\">Encryption:\u00a0<strong>STARTTLS<\/strong>\u00a0<\/li>\n\n\n\n<li id=\"htoc-authentication-enabled\">Authentication:\u00a0<strong>Enabled<\/strong>\u00a0<\/li>\n\n\n\n<li id=\"htoc-username-full-email-address\">Username: Full email address\u00a0<\/li>\n<\/ul>\n\n\n\n<p>Always send a&nbsp;<strong>test email<\/strong>&nbsp;after saving changes.&nbsp;<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-common-smtp-issues-and-fast-fixes\"><strong>Common SMTP Issues (And Fast Fixes)<\/strong>&nbsp;<\/h2>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td><strong>Issue<\/strong>&nbsp;<\/td><td><strong>Likely Cause<\/strong>&nbsp;<\/td><td><strong>Quick Fix<\/strong>&nbsp;<\/td><\/tr><tr><td>Cannot send mail&nbsp;<\/td><td>Wrong port&nbsp;<\/td><td>Use 587&nbsp;<\/td><\/tr><tr><td>Encryption error&nbsp;<\/td><td>SSL\/TLS mismatch&nbsp;<\/td><td>Match port + encryption&nbsp;<\/td><\/tr><tr><td>Timeout&nbsp;<\/td><td>ISP blocking&nbsp;<\/td><td>Try 2525&nbsp;<\/td><\/tr><tr><td>Auth failed&nbsp;<\/td><td>Login mismatch&nbsp;<\/td><td>Use full email address&nbsp;<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-best-practices-email-stability\"><strong>Best Practices (Email Stability)<\/strong>&nbsp;<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li id=\"htoc-use-587-starttls-wherever-possible\">Use\u00a0<strong>587 + STARTTLS<\/strong>\u00a0wherever possible\u00a0<\/li>\n\n\n\n<li id=\"htoc-avoid-port-25-for-email-clients\">Avoid port 25 for email clients\u00a0<\/li>\n\n\n\n<li id=\"htoc-keep-email-apps-updated\">Keep email apps updated\u00a0<\/li>\n\n\n\n<li id=\"htoc-pair-transport-security-with-spf-dkim-dmarc\">Pair transport security with\u00a0<strong>SPF, DKIM, DMARC<\/strong>\u00a0<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-our-scope-of-support\"><strong>Our&nbsp;<\/strong><a href=\"https:\/\/1grid.co.za\/knowledge\/1-grid-scope-of-support\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Scope of Support<\/strong><\/a><strong><\/strong>&nbsp;<\/h2>\n\n\n\n<p>If&nbsp;you\u2019re&nbsp;stuck and need any&nbsp;additional&nbsp;guidance or support,&nbsp;here\u2019s&nbsp;an outline of what we can do and what is not within&nbsp;our<strong>&nbsp;<\/strong><a href=\"https:\/\/1grid.co.za\/knowledge\/1-grid-scope-of-support\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Scope of Support<\/strong><\/a>.&nbsp;<\/p>\n\n\n\n<p><strong><\/strong><a href=\"https:\/\/1grid.co.za\/knowledge\/1-grid-scope-of-support\/#htoc-standard-support-included\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Included Support<\/strong><\/a><strong><\/strong>&nbsp;<\/p>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>What We Can Help With<\/strong><\/summary>\n<ul class=\"wp-block-list\">\n<li>Confirming correct SMTP settings\u00a0<\/li>\n\n\n\n<li>Verifying server availability\u00a0<\/li>\n\n\n\n<li>Guiding secure configuration\u00a0<\/li>\n\n\n\n<li>Testing mail flow\u00a0<\/li>\n<\/ul>\n<\/details>\n\n\n\n<p><strong><\/strong><a href=\"https:\/\/1grid.co.za\/knowledge\/1-grid-scope-of-support\/#htoc-11111111\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Outside Our Scope<\/strong><\/a><strong><\/strong>&nbsp;<\/p>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>What We Are Unable to Assist With<\/strong><\/summary>\n<ul class=\"wp-block-list\">\n<li>\u00a0ISP port blocking&nbsp;<\/li>\n\n\n\n<li>Device-specific restrictions&nbsp;<\/li>\n\n\n\n<li>Third-party app limitations&nbsp;<\/li>\n<\/ul>\n<\/details>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-faqs\"><strong>FAQs<\/strong>&nbsp;<\/h2>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>Q. Which SMTP port should I use?\u00a0<\/strong><\/summary>\n<p id=\"htoc-port-587-with-starttls-is-recommended-in-most-cases\">Port 587 with STARTTLS is recommended in most cases.\u00a0<\/p>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>Q. Is SSL still safe?\u00a0<\/strong><\/summary>\n<p id=\"htoc-tls-is-the-modern-standard-ssl-usually-refers-to-tls\">TLS is the modern standard. \u201cSSL\u201d usually refers to TLS.\u00a0<\/p>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>Q. Why does email work on one device but not another?\u00a0<\/strong><\/summary>\n<p id=\"htoc-different-ports-or-encryption-settings-are-often-the-cause\">Different ports or encryption settings are often the cause.\u00a0<\/p>\n<\/details>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary><strong>Q. Does encryption protect stored emails?\u00a0<\/strong><\/summary>\n<p id=\"htoc-no-it-protects-emails-during-transmission\">No, it protects emails\u00a0<strong>during transmission<\/strong>.\u00a0<\/p>\n<\/details>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-additional-resources\"><strong>Additional&nbsp;Resources<\/strong>&nbsp;<\/h2>\n\n\n\n<p><a href=\"https:\/\/1grid.co.za\/knowledge\/settings-to-configure-your-1grid-email-accounts-across-devices\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Settings to Configure Your 1-grid Email Accounts Across Devices<\/strong><\/a>\u00a0<br><a href=\"https:\/\/1grid.co.za\/knowledge\/what-is-the-difference-between-imap-and-pop\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>IMAP vs POP3: What\u2019s the Difference?<\/strong><\/a>\u00a0<br><a href=\"https:\/\/1grid.co.za\/knowledge\/troubleshooting-steps-for-email\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Basic Email Troubleshooting<\/strong><\/a>\u00a0<br><a href=\"https:\/\/1grid.co.za\/knowledge\/?s=spf&amp;ht-kb-search=1&amp;lang=\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>SPF, DKIM, and DMARC\u00a0Records for Email<\/strong><\/a>\u00a0<br><a href=\"https:\/\/1grid.co.za\/knowledge\/?s=email+security&amp;ht-kb-search=1&amp;lang=\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Email Security Best Practices<\/strong><\/a>\u00a0<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"htoc-need-additional-support\"><strong>Need Additional Support?<\/strong>&nbsp;<\/h2>\n\n\n\n<p><strong>We&#8217;re&nbsp;Here to&nbsp;<\/strong><a href=\"https:\/\/1grid.co.za\/knowledge\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>Help<\/strong><\/a><strong>:<\/strong>&nbsp;<\/p>\n\n\n\n<p>Understanding&nbsp;SMTP Ports and SSL-TLS Encryption&nbsp;doesn\u2019t&nbsp;have to feel&nbsp;technical&nbsp;with&nbsp;this&nbsp;easy-to-reference&nbsp;guide. Stuck?&nbsp;Contact our Support Team for&nbsp;clarity and&nbsp;guidance&nbsp;(<a href=\"https:\/\/1grid.co.za\/contact-us\/\" target=\"_blank\" rel=\"noreferrer noopener\"><strong>https:\/\/1grid.co.za\/contact-us\/<\/strong><\/a>).&nbsp;We&#8217;re&nbsp;ready&nbsp;to see how we can help!&nbsp;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>If\u00a0you\u2019ve\u00a0ever seen errors like \u201cCannot connect to SMTP server\u201d or \u201cEncryption mismatch\u201d,\u00a0the issue is usually not your mailbox;\u00a0it\u2019s\u00a0the port or security setting.\u00a0Understanding SMTP ports and SSL\/TLS encryption helps determine what might be causing sending issues with your emails.\u00a0 This guide will help you understand SMTP ports, SSL\/TLS encryption, and how&#8230;<\/p>\n","protected":false},"author":21,"comment_status":"closed","ping_status":"closed","template":"","format":"standard","meta":{"inline_featured_image":false,"footnotes":""},"ht-kb-category":[1173,1193,1194],"ht-kb-tag":[1496,1470,759,928,1637,1022,1046],"class_list":["post-34355","ht_kb","type-ht_kb","status-publish","format-standard","hentry","ht_kb_category-email","ht_kb_category-email-setup-config","ht_kb_category-email-troubleshooting","ht_kb_tag-email-security","ht_kb_tag-email-settings","ht_kb_tag-ports","ht_kb_tag-smtp","ht_kb_tag-ssl-tls-encryption","ht_kb_tag-tls","ht_kb_tag-troubleshooting"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v22.0 - 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