{"id":13432,"date":"2026-09-07T08:53:42","date_gmt":"2026-09-07T06:53:42","guid":{"rendered":"https:\/\/mybox.com\/help\/?post_type=manual_kb&#038;p=13432"},"modified":"2026-09-07T08:53:47","modified_gmt":"2026-09-07T06:53:47","slug":"email-works-in-webmail-but-not-in-outlook-apple-mail-or-thunderbird-diagnostic-faq","status":"publish","type":"manual_kb","link":"https:\/\/mybox.com\/help\/en\/knowledgebase\/email-works-in-webmail-but-not-in-outlook-apple-mail-or-thunderbird-diagnostic-faq\/","title":{"rendered":"Email works in webmail but not in Outlook, Apple Mail, or Thunderbird: diagnostic FAQ"},"content":{"rendered":"\n<div class=\"translation-block translation-block-merged\">\n<p class=\"wp-block-paragraph\">If your mailbox works in mybox Webmail but not in Outlook, Apple Mail, Thunderbird, or another email application, the mailbox is reachable through the browser. The email client has a separate connection or configuration problem. Check the client\u2019s server addresses, ports, and account settings.<\/p>\n\n\n\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_86 ez-toc-wrap-left counter-hierarchy ez-toc-counter ez-toc-custom ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/mybox.com\/help\/en\/knowledgebase\/email-works-in-webmail-but-not-in-outlook-apple-mail-or-thunderbird-diagnostic-faq\/#What_does_working_webmail_tell_me\" >What does working webmail tell me?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/mybox.com\/help\/en\/knowledgebase\/email-works-in-webmail-but-not-in-outlook-apple-mail-or-thunderbird-diagnostic-faq\/#What_is_the_most_likely_cause\" >What is the most likely cause?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/mybox.com\/help\/en\/knowledgebase\/email-works-in-webmail-but-not-in-outlook-apple-mail-or-thunderbird-diagnostic-faq\/#How_should_I_check_the_email_client\" >How should I check the email client?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/mybox.com\/help\/en\/knowledgebase\/email-works-in-webmail-but-not-in-outlook-apple-mail-or-thunderbird-diagnostic-faq\/#Why_can_receiving_and_sending_behave_differently\" >Why can receiving and sending behave differently?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/mybox.com\/help\/en\/knowledgebase\/email-works-in-webmail-but-not-in-outlook-apple-mail-or-thunderbird-diagnostic-faq\/#Why_are_sent_messages_missing_in_webmail\" >Why are sent messages missing in webmail?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/mybox.com\/help\/en\/knowledgebase\/email-works-in-webmail-but-not-in-outlook-apple-mail-or-thunderbird-diagnostic-faq\/#Do_Outlook_Thunderbird_and_Apple_Mail_use_the_same_setup\" >Do Outlook, Thunderbird, and Apple Mail use the same setup?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/mybox.com\/help\/en\/knowledgebase\/email-works-in-webmail-but-not-in-outlook-apple-mail-or-thunderbird-diagnostic-faq\/#What_if_the_mailbox_also_includes_a_calendar\" >What if the mailbox also includes a calendar?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/mybox.com\/help\/en\/knowledgebase\/email-works-in-webmail-but-not-in-outlook-apple-mail-or-thunderbird-diagnostic-faq\/#FAQ\" >FAQ<\/a><\/li><\/ul><\/nav><\/div>\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"What_does_working_webmail_tell_me\"><\/span>What does working webmail tell me?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Webmail and an email client are two different ways to access the same mailbox. A successful sign-in at <span>mybox Webmail<\/span> shows that the mailbox can be accessed through the browser. It does not configure Outlook, Apple Mail, Thunderbird, or another application automatically.<\/p>\n\n\n\n<\/div>\n\n<div id=\"mybox-4033098366\" class=\"mybox-content mybox-entity-placement\"><div class=\"early-access-banner-inpost\">\r\n  <div class=\"banner-left-inpost\">\r\n    <div class=\"icon-box-inpost\">\r\n      <img decoding=\"async\" src=\"https:\/\/mybox.com\/help\/wp-content\/uploads\/2026\/02\/square-info-icon.svg\" alt=\"Info\">\r\n    <\/div>\r\n    <div class=\"text-box-inpost\">\r\n      <span class=\"label-inpost\"><span class=\"translation-block translation-block-banner-text\">Early access<\/span><\/span>\r\n      <h4><span class=\"translation-block translation-block-banner-text\">Still need help?<\/span><\/h4>\r\n      <p><span class=\"translation-block translation-block-banner-text\">Contact our customer service team.<\/span><\/p>\r\n    <\/div>\r\n  <\/div>\r\n\r\n  <div class=\"banner-right-inpost\">\r\n    <a href=\"https:\/\/panel.mybox.com\/helpdesk2\/v\/list\/\" class=\"banner-button-inpost\"><span class=\"translation-block translation-block-banner-text\">Message us<\/span><\/a>\r\n  <\/div>\r\n<\/div><\/div>\n\n<div class=\"translation-block translation-block-merged\"><p class=\"wp-block-paragraph\">An email client must be configured with the correct server addresses and ports before it can send and receive messages. mybox describes Outlook, Thunderbird, and Apple Mail as examples of email clients and provides manual configuration settings for connecting them to a mybox mailbox. <a href=\"https:\/\/mybox.com\/help\/knowledgebase\/how-to-configure-the-email-client\/\">See the mybox email client configuration instructions<\/a>.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"What_is_the_most_likely_cause\"><\/span>What is the most likely cause?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The most common cause is an incorrect or incomplete email client configuration. The client may have an incorrect server address, an incorrect port, or settings that do not match the mailbox connection details. Webmail can continue to work because it uses the mybox web interface rather than the settings saved in the email application.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Start with the configuration values shown in the mybox instructions. Compare them with the values entered in the affected client. Check the account configuration rather than changing unrelated mailbox settings.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"How_should_I_check_the_email_client\"><\/span>How should I check the email client?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Identify the affected application.<\/strong> Note whether the problem occurs in Outlook, Thunderbird, Apple Mail, or another mail application.<\/li>\n\n\n\n<li><strong>Open the account settings.<\/strong> Find the configuration for the mybox mailbox in that application.<\/li>\n\n\n\n<li><strong>Compare the server addresses.<\/strong> Use the server addresses provided by mybox instead of relying on values copied from another account.<\/li>\n\n\n\n<li><strong>Compare the ports.<\/strong> The email client must use the ports specified for the relevant connection in the mybox configuration instructions.<\/li>\n\n\n\n<li><strong>Save the settings.<\/strong> Reconnect the account after the values have been checked.<\/li>\n<\/ol>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Why_can_receiving_and_sending_behave_differently\"><\/span>Why can receiving and sending behave differently?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Email clients use separate settings for receiving and sending mail. A client can therefore show one type of failure while another part of the account continues to work. Check the server address and port for each part of the configuration, not only the first value shown in the account settings.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Why_are_sent_messages_missing_in_webmail\"><\/span>Why are sent messages missing in webmail?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A message sent from an email client may not appear in the Sent folder in mybox Webmail. This is usually caused by the way the email client stores sent messages. The message can have been sent successfully while the client saves its copy in a location that is different from the webmail Sent folder. <a href=\"https:\/\/mybox.com\/help\/knowledgebase\/why-cant-i-see-messages-sent-from-an-email-client-in-mail-mybox-com\/\">Read the mybox explanation of missing sent messages<\/a>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This symptom is separate from a complete connection failure. If the client sends messages but they do not appear in the webmail Sent folder, check where that client stores sent messages. If the client cannot connect or cannot send at all, first check the server addresses and ports.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Do_Outlook_Thunderbird_and_Apple_Mail_use_the_same_setup\"><\/span>Do Outlook, Thunderbird, and Apple Mail use the same setup?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">They are all email clients, but their account screens and setting names can differ. The required connection details still need to be entered in the application being used. Use the mybox email client settings, then locate the matching server and port fields in Outlook, Thunderbird, or Apple Mail.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"What_if_the_mailbox_also_includes_a_calendar\"><\/span>What if the mailbox also includes a calendar?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Calendar access is configured separately from email access. If you use a third-party email client for the calendar, mybox provides calendar configuration tutorials for CalDAV in macOS Calendar and Outlook. <a href=\"https:\/\/mybox.com\/help\/knowledgebase\/how-to-configure-the-calendar-in-email-clients\/\">See the mybox calendar configuration instructions<\/a>.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"FAQ\"><\/span>FAQ<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary>Does working webmail prove that Outlook is configured correctly?<\/summary>\n<p class=\"wp-block-paragraph\"><\/p>\n<\/details>\n\n\n\n<p class=\"wp-block-paragraph\">No. Webmail access and email client access use different interfaces. The client still needs the correct server addresses and ports.<\/p>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary>Should I change the mailbox if webmail works?<\/summary>\n<p class=\"wp-block-paragraph\"><\/p>\n<\/details>\n\n\n\n<p class=\"wp-block-paragraph\">Begin with the email client configuration. Compare its server addresses and ports with the mybox settings before changing other mailbox options.<\/p>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary>Is a missing Sent message always a sending failure?<\/summary>\n<p class=\"wp-block-paragraph\"><\/p>\n<\/details>\n\n\n\n<p class=\"wp-block-paragraph\">No. An email can be sent successfully while the client stores its copy outside the Sent folder shown in mybox Webmail.<\/p>\n<\/div>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"template":"","format":"standard","manualknowledgebasecat":[30],"manual_kb_tag":[],"class_list":["post-13432","manual_kb","type-manual_kb","status-publish","format-standard","hentry","manualknowledgebasecat-configuration-of-email-clients"],"_links":{"self":[{"href":"https:\/\/mybox.com\/help\/en\/wp-json\/wp\/v2\/manual_kb\/13432","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mybox.com\/help\/en\/wp-json\/wp\/v2\/manual_kb"}],"about":[{"href":"https:\/\/mybox.com\/help\/en\/wp-json\/wp\/v2\/types\/manual_kb"}],"author":[{"embeddable":true,"href":"https:\/\/mybox.com\/help\/en\/wp-json\/wp\/v2\/users\/1"}],"version-history":[{"count":1,"href":"https:\/\/mybox.com\/help\/en\/wp-json\/wp\/v2\/manual_kb\/13432\/revisions"}],"predecessor-version":[{"id":13440,"href":"https:\/\/mybox.com\/help\/en\/wp-json\/wp\/v2\/manual_kb\/13432\/revisions\/13440"}],"wp:attachment":[{"href":"https:\/\/mybox.com\/help\/en\/wp-json\/wp\/v2\/media?parent=13432"}],"wp:term":[{"taxonomy":"manualknowledgebasecat","embeddable":true,"href":"https:\/\/mybox.com\/help\/en\/wp-json\/wp\/v2\/manualknowledgebasecat?post=13432"},{"taxonomy":"manual_kb_tag","embeddable":true,"href":"https:\/\/mybox.com\/help\/en\/wp-json\/wp\/v2\/manual_kb_tag?post=13432"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}