{"id":2269,"date":"2020-07-16T00:00:00","date_gmt":"2020-07-16T00:00:00","guid":{"rendered":"https:\/\/www.mailboxvalidator.com\/resources3\/articles\/how-to-block-invalid-email-sign-up-in-whmcs\/"},"modified":"2020-07-16T00:00:00","modified_gmt":"2020-07-16T00:00:00","password":"","slug":"how-to-block-invalid-email-sign-up-in-whmcs","status":"publish","type":"docs","link":"https:\/\/www.mailboxvalidator.com\/resources\/articles\/how-to-block-invalid-email-sign-up-in-whmcs\/","title":{"rendered":"How to block invalid email sign up in WHMCS?"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\">Introduction<\/h2>\n\n\n\n<p>Selling things online is a huge industry and anyone can do it. All you need is a computer with an Internet connection. Merchants are able to get more customers easily. It is because online business is operating 24\/7 non-stop. As long as the delivery service is still operating, buyers can rest assured they&#8217;ll get their items. There are lots of benefits to operating an online business, however merchants must be careful as well. The reason is some people tend to commit fraud online. One of the tell-tale signs of such people is that they will use a disposable email address when committing fraud. This is to prevent them from being tracked by law enforcement. As such, merchants will suffer huge losses from being the victim of fraud.<\/p>\n\n\n\n<p>To prevent such things from happening, sellers are encouraged to use third party addon such as the <a href=\"https:\/\/marketplace.whmcs.com\/product\/5533-mailboxvalidator-email-validator\" target=\"_blank\" rel=\"noopener\">MailboxValidator WHMCS addon<\/a>. This addon can save the seller time and effort, as it requires minimal steps to set up and run.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"setup-the-mailboxvalidator-opencart-extension\">Setup the MailboxValidator WHMCS addon<\/h2>\n\n\n\n<p>Before you start to setup and use the addon, you need to get a free API key from <a href=\"https:\/\/www.mailboxvalidator.com\/plans#api\">MailboxValidator<\/a>. After that, download the <a href=\"https:\/\/marketplace.whmcs.com\/product\/5533-mailboxvalidator-email-validator\" target=\"_blank\" rel=\"noopener\">latest version of the addon<\/a>. Follow the steps below to setup the addon:<\/p>\n\n\n\n<ol class=\"wp-block-list\"><li>Unzip the downloaded zip file. After that, upload all files under whmcs\/ to the WHMCS installation folder.<\/li><li>In the WHMCS admin page, Setup &gt; Addon Modules, activate MailboxValidator Email Validator.<a href=\"https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_25_52.png\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-1464 size-large\" src=\"https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_25_52-1024x49.png\" alt=\"Activate MailboxValidator Email Validator module in admin setup addon page\" width=\"920\" height=\"44\" srcset=\"https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_25_52-1024x49.png 1024w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_25_52-300x14.png 300w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_25_52-768x37.png 768w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_25_52-50x2.png 50w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_25_52-920x44.png 920w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_25_52-600x29.png 600w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_25_52-320x15.png 320w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_25_52.png 1258w\" sizes=\"auto, (max-width: 920px) 100vw, 920px\" \/><\/a><\/li><li>Configure the addon to enable Full Administrator access.<a href=\"https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_21_48.png\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-1462 size-large\" src=\"https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_21_48-1024x167.png\" alt=\"Enable Full Administrator access for MailboxValidator Email Validator\" width=\"920\" height=\"150\" srcset=\"https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_21_48-1024x167.png 1024w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_21_48-300x49.png 300w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_21_48-768x125.png 768w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_21_48-50x8.png 50w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_21_48-920x150.png 920w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_21_48-600x98.png 600w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_21_48-320x52.png 320w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-15_21_48.png 1277w\" sizes=\"auto, (max-width: 920px) 100vw, 920px\" \/><\/a><\/li><li>Go to Addons &gt; MailboxValidator Email Validator for further customization.<\/li><li>You will be required to configure the settings. For example, you will need to enter the API key in the API key field. In the same page, there are a few email validators that are available, which are the valid, disposable, free and role-based email validator. You will need to switch on or off for each email validator.<a href=\"https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_33_07.png\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-1463 size-large\" src=\"https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_33_07-1024x645.png\" alt=\"Configure settings for MailboxValidator Email Validator module\" width=\"920\" height=\"579\" srcset=\"https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_33_07-1024x645.png 1024w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_33_07-300x189.png 300w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_33_07-768x484.png 768w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_33_07-50x31.png 50w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_33_07-920x579.png 920w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_33_07-600x378.png 600w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_33_07-320x201.png 320w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_33_07.png 1304w\" sizes=\"auto, (max-width: 920px) 100vw, 920px\" \/><\/a><\/li><\/ol>\n\n\n\n<figure class=\"wp-block-image aligncenter\"><a href=\"https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_48_50.png\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"369\" src=\"https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_48_50-1024x369.png\" alt=\"Example output of entering disposable email address\" class=\"wp-image-1468\" srcset=\"https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_48_50-1024x369.png 1024w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_48_50-300x108.png 300w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_48_50-768x277.png 768w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_48_50-50x18.png 50w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_48_50-920x332.png 920w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_48_50-600x216.png 600w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_48_50-320x115.png 320w, https:\/\/www.mailboxvalidator.com\/resources\/wp-content\/uploads\/2020\/07\/screenshot-my.dev-2020.07.14-14_48_50.png 1162w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/a><\/figure>\n\n\n\n<p>The various validators function similarly with minor differences. The valid email validator will validate the email address based on the status of the email address. The disposable email validator will check whether the email address is coming from a disposable email address service provider or not. Last but not least, the free email validator will check if the email address is coming from a free email address service provider or not.<\/p>\n\n\n\n<figure class=\"wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<iframe loading=\"lazy\" title=\"Prevent Spam Sign up in WHMCS using Email Validator Service\" width=\"500\" height=\"281\" src=\"https:\/\/www.youtube.com\/embed\/aWRVrsR05yg?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe>\n<\/div><\/figure>\n\n\n\n<div style=\"height:32px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"has-text-align-center wp-block-heading\">Get started with MailboxValidator<\/h2>\n\n\n\n<p class=\"has-text-align-center\">Improve your email deliverability and sender reputation in email marketing.<\/p>\n\n\n\n<p class=\"has-text-align-center\">Register today and clean your email lists for <strong>FREE<\/strong>!<\/p>\n\n\n\n<p class=\"has-text-align-center\"><a class=\"maxbutton-1 maxbutton maxbutton-sign-up-bulk-trial\" target=\"_blank\" title=\"No Setup Fee. Sign Up Trial Today!\" rel=\"noopener\" href=\"https:\/\/www.mailboxvalidator.com\/plans#mailboxvalidator-freesignup\"><span class='mb-text'>GET STARTED FOR FREE<\/span><\/a><\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n","protected":false},"excerpt":{"rendered":"<p>Introduction Selling things online is a huge industry and anyone can do it. All you need is a computer with [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"doc_category":[67],"doc_tag":[],"class_list":["post-2269","docs","type-docs","status-publish","hentry","doc_category-mailboxvalidator-articles"],"year_month":"2026-05","word_count":417,"total_views":0,"reactions":{"happy":0,"normal":0,"sad":0},"author_info":{"name":"mbv_editor","author_nicename":"mbv_editor","author_url":"https:\/\/www.mailboxvalidator.com\/resources\/author\/mbv_editor\/"},"doc_category_info":[{"term_name":"MailboxValidator Articles","term_url":"https:\/\/www.mailboxvalidator.com\/resources\/article-categories\/mailboxvalidator-articles\/"}],"doc_tag_info":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.6 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>How to block invalid email sign up in WHMCS? -<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.mailboxvalidator.com\/resources\/articles\/how-to-block-invalid-email-sign-up-in-whmcs\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"How to block invalid email sign up in WHMCS? -\" \/>\n<meta property=\"og:description\" content=\"Introduction Selling things online is a huge industry and anyone can do it. 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