WP Mail SMTP by WPForms的作者是WPForms，目前有1+ 百万个有效安装。已经Tested with 5.4.1版本的wordpress。
WORDPRESS 电子邮件 SMTP 寄件插件
Having problems with your WordPress site not sending emails? You’re not alone. Over 1 million websites use WP Mail SMTP to send their emails reliably.
Our goal is to make email deliverability easy and reliable. We want to ensure your emails reach the inbox.
WP Mail SMTP fixes your email deliverability by reconfiguring WordPress to use a proper SMTP provider when sending emails.
SMTP (Simple Mail Transfer Protocol) is an industry standard for sending emails. Proper SMTP configuration helps increase email deliverability by using authentication.
Popular email clients like Gmail, Yahoo, and Office 365 are in a constant battle with email spammers. One of the things they look at is if an email is originating from the location it claims to be originating from.
If the proper authentication isn’t there, then emails either go in the SPAM folder or worst, don’t get delivered at all.
WP MAIL SMTP如何工作？
WP Mail SMTP plugin easily resolves email delivery problems by improving and changing how your WordPress site sends email. We reconfigure the wp_mail() function to either use proper SMTP host credentials or leverage a built-in SMTP mail provider.
When using one of our built-in SMTP mail provider integrations (recommended), emails are sent using the provider’s direct API. This means even if your web host is blocking SMTP ports, your emails still send successfully.
谷歌翻译：WP Mail SMTP插件包括四种不同的SMTP设置选项：
WP Mail SMTP插件包含许多不同的SMTP设置选项：
Pepipost SMTP (Recommended)
Microsoft SMTP (Outlook.com and Office 365) [Pro]
Amazon SES SMTP [Pro]
谷歌翻译：我们决定将其全部集于一身，而不是让用户为不同的SMTP提供商使用不同的SMTP插件和工作流程。 这就是使WP Mail SMTP成为WordPress的最佳SMTP解决方案的原因。
SMTP.com is a recommended transactional email service.
With over 22 years of email delivery expertise, SMTP.com has been around for almost as long as email itself. They are known among internet providers as one of the most reliable senders on the internet.
Their easy integration process lets you start sending emails in minutes and benefit from years of experience. SMTP.com provides users 10,000 free emails the first 30 days.
Read our SMTP.com documentation for more details.
Pepipost is a recommended transactional email service.
Every month they delivers over 8 billion emails from 20,000+ customers.
Their mission is to reliably send emails in the most efficient way and at the most disruptive pricing ever.
Pepipost provides users 30,000 emails the first 30 days.
Read our Pepipost documentation for more details.
They serve 80,000+ growing companies around the world and send over 30 million emails each day.
Their email deliverability experts are constantly at work optimizing the reliability and speed of their SMTP infrastructure. Sendinblue provides users 300 free emails per day.
Read our Sendinblue documentation for more details.
Mailgun SMTP is a popular SMTP service provider that allows you to send large quantities of emails. They provide 5,000 free emails per month for 3 months.
谷歌翻译：WP Mail SMTP插件提供与MailGun的本机集成。 您所要做的就是连接您的Mailgun帐户，您将提高您的电子邮件传送能力。
Read our Mailgun documentation for more details.
谷歌翻译：SendGrid有一个免费的SMTP计划，您可以使用它每天发送多达100封电子邮件。 通过我们的本机SendGrid SMTP集成，您可以在WordPress站点上轻松安全地设置SendGrid SMTP。
Read our SendGrid documentation for more details.
谷歌翻译：博主和小企业主通常不想使用第三方SMTP服务。 那么您可以使用Gmail或G Suite帐户来收发SMTP电子邮件。
谷歌翻译：与其他Gmail SMTP插件不同，我们的Gmail SMTP选项使用OAuth对您的Google帐户进行身份验证，确保您的登录信息100％安全。
Read our Gmail documentation for more details.
MICROSOFT SMTP (OUTLOOK.COM AND OFFICE 365)
Many business use Outlook.com or Office 365 to their to power their email. For those users, the Microsoft mailer can be a great option. This integration allows you to use your existing Outlook.com or Office 365 account to send your emails reliably.
AMAZON SES SMTP
Advanced or technical users can harness the power of Amazon AWS (Amazon Web Services) with the Amazon SES mailer. With this integration, you can send a high volume of emails at a very reasonable rate.
Read our Amazon SES documentation for more details.
WP Mail SMTP插件可以用于常见的电子邮件服务如Gmail、Yahoo、Outlook、Microsoft Live，也可用于其他提供SMTP的电子邮件服务。
选择SSL / TLS加密。
我们希望您发现WP Mail SMTP插件有用！
WP MAIL SMTP PRO
In addition to native Microsoft and Amazon SES integrations, WP Mail SMTP Pro provides access to many other powerful features and services.
Click here to purchase WP Mail SMTP Pro now!
Email Logging lets you log and view all emails sent from your site. Email logs are helpful for storing emails for your records, auditing outgoing emails, and debugging during site development.
MANAGE WORDPRESS EMAILS AND NOTIFICATIONS
The Manage Notification feature gives you full control over which email notifications WordPress sends. This means you can disable different WordPress notification emails. Don’t want to receive emails when new users are created? No problem, turn it off.
We provide limited support for the WP Mail SMTP plugin on the WordPress.org forums. Access to our world class one-on-one email support is available to WP Mail SMTP Pro users.
WHITE GLOVE SETUP
Our White Glove Setup service is a great option that anyone can benefit from. Whether you don’t have the time or maybe you feel a bit in over your head – we’ve got you covered.
You can sit back and relax while we set up everything for you. White glove setup includes WP Mail SMTP plugin installation and setup, configuration adjustments to your DNS for proper email domain name verification, Mailgun setup, and final testing to confirm everything is passing with flying colors.
The WP Mail SMTP team takes security very seriously. Not only does the plugin follow all security best practices, but we have several options available to ensure your site is safe and secure.
Direct SMTP mailer integrations (recommended), such as SMTP.com, Pepipost and Mailgun, use the official provider APIs. This means you never enter your username or password in the plugin settings and these credentials are not stored in the database. Instead, we use tokens or API keys which are much more secure.
When using Other SMTP mailer, we provide the option to insert your password in your wp-config.php file, so it’s not visible in your WordPress settings or saved in the database.
WP Mail SMTP插件最初是由Callum Macdonald所开发。 现由WPForms幕后的团队所拥有和维护，WPForms是很受欢迎的WordPress拖放表单生成器。
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