SendForce Mail SMTP Relay – SMTP and vs Ultimate WP Mail

SendForce Mail Relay is a free, open-source WordPress SMTP and email-API plugin that fixes the “WordPress emails not being delivered” problem. Send WooCommerce order emails, Contact Form 7 / WPForms / Gravity Forms submissions, password resets, registration confirmations, and any other wp_mail() traffic through Amazon SES, SendGrid, Mailgun, Brevo (Sendinblue), Postmark, Zoho ZeptoMail, Gmail API, Microsoft 365, or any standard SMTP server — with full email logging, queue, retry, and failure alerts. Why SendForce Mail Relay Free and open-source. Every feature is included — no premium tier, no email-volume cap, no provider paywall. 24+ providers, one plugin. Built-in presets and HTTP API integrations for major transactional email services — pick what fits your budget, deliverability needs, and region. Built-in debugging. Live SMTP debug log on test email, raw API request/response capture in the email log, “Copy Debug Info” button for support tickets, and WP-CLI commands. Designed for developers and agencies who need to diagnose email problems fast. Multiple connections with automatic fallback. Configure a primary connection (e.g. Amazon SES) plus a fallback (e.g. Mailgun). If the primary returns an error, the fallback takes over — no email lost. Supported email providers HTTP API sending (recommended — faster and more reliable than SMTP): Amazon SES (AWS Simple Email Service) SendGrid (by Twilio) Mailgun (by Sinch) Brevo (formerly Sendinblue) SparkPost Postmark Zoho ZeptoMail Microsoft 365 / Outlook (Microsoft Graph API) Gmail / Google Workspace (Gmail API) SMTP2GO SMTP.com Elastic Email SocketLabs Moosend SendLayer Mailjet MailerSend Mandrill (by Mailchimp) Resend Netcore Email API (formerly Pepipost) SMTP sending (works with any provider, including custom servers): Gmail / Google Workspace SMTP (smtp.gmail.com) Microsoft 365 / Outlook SMTP (smtp.office365.com) Yahoo Mail SMTP Zoho Mail SMTP Turbo SMTP Any other SMTP server (host, port, username, password) Features Multiple connections with automatic fallback — configure a primary connection (e.g. Amazon SES) plus a fallback (e.g. Mailgun, SMTP, or PHP mail). If the primary returns an error, the fallback is attempted automatically. Both attempts are logged so you have a full audit trail; recovered emails carry a “Recovered via fallback” badge in the log detail view. Smart Routing Rules — send different emails through different connections based on rules you define. Match by recipient domain, recipient pattern (glob), sender email or domain, source plugin (auto-detected for WooCommerce, Contact Form 7, WPForms, Gravity Forms, Ninja Forms, Fluent Forms, Forminator, Easy Digital Downloads, MemberPress, LearnDash, MailPoet, BuddyPress, bbPress and more), subject contains, time of day, or weekday. Rules are evaluated top-down (first match wins) and can target a single connection, a round-robin pool, or WordPress phpmail(). Includes inline rule editor, master enable/disable toggle, “Test Routing” tool, and a “via rule:” badge on the Email Log so you can see exactly which rule fired for any send. One-click provider presets — pre-filled host, port, encryption, and API endpoint for every supported provider. Just paste your API key or password. Email Log — every outgoing email logged with status, recipient, subject, headers, error message, and timestamp. Filter by status, search by keyword, filter by date range, export to CSV or JSON. Email Queue with retry — queue mode prevents rate-limit errors and timeouts on bulk sends. Failed emails auto-retry on exponential backoff (5 min → 15 min → 45 min). Email Test page — send a test email with live SMTP debug log output. Diagnose connection problems instantly. Failure alerts — push delivery failures to Telegram, Slack, Discord, Microsoft Teams, Google Chat, Pushover, or any custom webhook. Sender Identity override — force every email to use a custom From name and From address site-wide. Conflict detection — warns you if another SMTP plugin (WP Mail SMTP, FluentSMTP, Easy WP SMTP, Post SMTP, etc.) is active so you can deactivate it before things break. Encrypted credential storage — SMTP passwords and API keys are encrypted at rest using AES-256-CBC with a dedicated per-site key, so they survive security-key/salt regeneration. WP-CLI commands — wp sendforce test, wp sendforce queue process, wp sendforce log list, wp sendforce sysinfo. Developer hooks — sendforce_before_send, sendforce_after_send, sendforce_log_entry, sendforce_api_request, sendforce_api_response for extending the plugin without forking. WP_DEBUG_LOG integration — optional mirroring of SMTP and API debug output to debug.log. Automatic log cleanup — configurable retention period (default 30 days). Privacy-friendly — optional disable of email-body logging for GDPR / privacy compliance. Multisite compatible. Works with all major WordPress plugins SendForce Mail Relay hooks into WordPress’s core wp_mail() function, so it works with every plugin that sends email — including WooCommerce, Easy Digital Downloads, Contact Form 7, WPForms, Gravity Forms, Ninja Forms, Fluent Forms, Forminator, MemberPress, LearnDash, BuddyPress, bbPress, MailPoet (transactional), and any custom plugin or theme that uses wp_mail(). External Services SendForce Mail Relay is an email-delivery plugin. It does NOT connect to any external service automatically. A connection is made ONLY after you explicitly configure a provider and either (a) WordPress sends an outgoing email, or (b) you click “Send Test Email”, or (c) you enable a notification channel and an email-failure alert is dispatched. For each configured email provider, the data sent on every send is the same set of fields WordPress would otherwise hand to the local mail() function: the recipient address(es), CC, BCC, Reply-To, From name/address, subject, message body, headers, and attachments. No additional telemetry or analytics is transmitted by this plugin. For each configured notification channel (Telegram, Slack, Discord, Microsoft Teams, Google Chat, Pushover, custom Webhook), the data sent is a short status message you compose in the plugin (default: failed-delivery summary or daily summary). Email-delivery providers (configurable in Settings → Connections) SendGrid (by Twilio) * Service: https://sendgrid.com * When data is sent: every WordPress email when SendGrid is the active connection, plus on test-email click. * Endpoint: https://api.sendgrid.com/v3/mail/send * Privacy Policy: https://www.twilio.com/en-us/legal/privacy * Terms of Service: https://www.twilio.com/en-us/legal/tos Mailgun (by Sinch) * Service: https://www.mailgun.com * When data is sent: same as above, but to Mailgun. * Endpoint: https://api.mailgun.net/v3/{domain}/messages (US) or https://api.eu.mailgun.net/v3/{domain}/messages (EU). * Privacy Policy: https://www.mailgun.com/legal/privacy-policy/ * Terms of Service: https://www.mailgun.com/legal/terms/ Amazon SES (AWS Simple Email Service) * Service: https://aws.amazon.com/ses/ * When data is sent: same. * Endpoint: https://email.{region}.amazonaws.com/v2/email/outbound-emails (region you select). * Privacy Policy: https://aws.amazon.com/privacy/ * Terms of Service: https://aws.amazon.com/service-terms/ Brevo (formerly Sendinblue) * Service: https://www.brevo.com * Endpoint: https://api.brevo.com/v3/smtp/email * Privacy Policy: https://www.brevo.com/legal/privacypolicy/ * Terms of Service: https://www.brevo.com/legal/termsofuse/ SparkPost * Service: https://www.sparkpost.com * Endpoint: https://api.sparkpost.com/api/v1/transmissions * Privacy Policy: https://www.sparkpost.com/policies/privacy/ * Terms of Service: https://www.sparkpost.com/policies/tou/ Postmark * Service: https://postmarkapp.com * Endpoint: https://api.postmarkapp.com/email * Privacy Policy: https://postmarkapp.com/privacy-policy * Terms of Service: https://postmarkapp.com/terms-of-service Elastic Email * Service: https://elasticemail.com * Endpoint: https://api.elasticemail.com/v4/emails * Privacy Policy: https://elasticemail.com (linked from the site footer; Elastic Email does not publish a stable deep-link URL) * Terms of Service: https://elasticemail.com (linked from the site footer; Elastic Email does not publish a stable deep-link URL) SMTP2GO * Service: https://www.smtp2go.com * Endpoint: https://api.smtp2go.com/v3/email/send * Privacy Policy: https://www.smtp2go.com/privacy/ * Terms of Service: https://www.smtp2go.com/terms/ Netcore Email API (formerly Pepipost) * Service: https://netcorecloud.com * Endpoint: https://emailapi.netcorecloud.net/v5/mail/send * Privacy Policy: https://netcorecloud.com/privacy-policy * Terms of Service: https://netcorecloud.com (request the latest terms via the contact form on the homepage; Netcore does not publish a stable terms-of-use URL). SMTP.com * Service: https://www.smtp.com * Endpoint: https://api.smtp.com/v4/messages * Privacy Policy: https://www.smtp.com/policies/privacy-policy/ * Terms of Service: https://www.smtp.com/legal/terms/ SocketLabs * Service: https://www.socketlabs.com * Endpoint: https://inject.socketlabs.com/api/v1/email * Privacy Policy: https://www.socketlabs.com/legal/privacy-policy/ * Terms of Service: https://www.socketlabs.com/legal/ Moosend (by Sitecore) * Service: https://moosend.com * Endpoint: https://api.moosend.com/v3/ * Privacy Policy: https://moosend.com/privacy-policy/ * Terms of Service: https://moosend.com/terms/ SendLayer * Service: https://sendlayer.com * Endpoint: https://console.sendlayer.com/api/v1/email * Privacy Policy: https://www.sendlayer.com/privacy-policy/ * Terms of Service: https://www.sendlayer.com/terms-of-service/ Mailjet (by Sinch) * Service: https://www.mailjet.com * Endpoint: https://api.mailjet.com/v3.1/send * Privacy Policy: https://sinch.com/legal/privacy-notice/ * Terms of Service: https://sinch.com/legal/ MailerSend * Service: https://www.mailersend.com * Endpoint: https://api.mailersend.com/v1/email * Privacy Policy: https://www.mailersend.com/legal/privacy-policy * Terms of Service: https://www.mailersend.com/legal/terms-of-use Mandrill (by Mailchimp) * Service: https://mailchimp.com/developer/transactional/ * Endpoint: https://mandrillapp.com/api/1.0/messages/send.json * Privacy Policy: https://mailchimp.com/legal/privacy/ * Terms of Service: https://mailchimp.com/legal/terms/ Resend * Service: https://resend.com * Endpoint: https://api.resend.com/emails * Privacy Policy: https://resend.com/legal/privacy-policy * Terms of Service: https://resend.com/legal/terms-of-service Zoho ZeptoMail * Service: https://www.zoho.com/zeptomail/ * Endpoint: https://api.zeptomail.com/v1.1/email * Privacy Policy: https://www.zoho.com/privacy.html * Terms of Service: https://www.zoho.com/zeptomail/terms.html Microsoft 365 / Outlook (Microsoft Graph API and SMTP) * Service: https://www.microsoft.com/microsoft-365 * Endpoint (API): https://graph.microsoft.com/v1.0/users/{user}/sendMail (OAuth token from https://login.microsoftonline.com/{tenant}/oauth2/v2.0/token) * Endpoint (SMTP): smtp.office365.com:587 * Privacy Policy: https://privacy.microsoft.com/en-US/privacystatement * Terms of Service: https://www.microsoft.com/en-us/servicesagreement/ Gmail / Google Workspace (Gmail API and SMTP) * Service: https://workspace.google.com * Endpoint (API): https://gmail.googleapis.com/gmail/v1/users/me/messages/send (OAuth token from https://oauth2.googleapis.com/token) * Endpoint (SMTP): smtp.gmail.com:587 * Privacy Policy: https://policies.google.com/privacy * Terms of Service: https://policies.google.com/terms Notification channels (configurable in Settings → Alerts) These services are contacted ONLY when a notification channel is enabled AND a delivery failure (or daily-summary) event triggers an alert. The data sent is the short status text shown in the plugin’s alert preview. Telegram (Bot API) * Service: https://telegram.org * When data is sent: when a Telegram channel is enabled, a failed-delivery alert or daily-summary alert is generated. * Endpoint: https://api.telegram.org/bot{token}/sendMessage * Privacy Policy: https://telegram.org/privacy * Terms of Service: https://telegram.org/tos Pushover * Service: https://pushover.net * Endpoint: https://api.pushover.net/1/messages.json * Privacy Policy: https://pushover.net/privacy * Terms of Service: https://pushover.net/terms Slack (Incoming Webhooks) * Service: https://slack.com * Endpoint: the webhook URL you paste (https://hooks.slack.com/services/…). * Privacy Policy: https://slack.com/trust/privacy/privacy-policy * Terms of Service: https://slack.com/legal Discord (Webhooks) * Service: https://discord.com * Endpoint: the webhook URL you paste (https://discord.com/api/webhooks/…). * Privacy Policy: https://discord.com/privacy * Terms of Service: https://discord.com/terms Microsoft Teams (Incoming Webhooks) * Service: https://www.microsoft.com/microsoft-teams/ * Endpoint: the Teams webhook URL you paste. * Privacy Policy: https://privacy.microsoft.com/en-US/privacystatement * Terms of Service: https://www.microsoft.com/en-us/servicesagreement/ Google Chat (Incoming Webhooks) * Service: https://chat.google.com * Endpoint: the Google Chat webhook URL you paste. * Privacy Policy: https://policies.google.com/privacy * Terms of Service: https://workspace.google.com/terms/premier_terms.html Custom Webhook * When data is sent: when a custom Webhook channel is enabled and an alert is generated, a JSON payload is POSTed to the URL you paste. * Endpoint: the URL you paste. * Privacy Policy / Terms: governed by the operator of the URL you provide. Bundled third-party libraries (no network call) Chart.js (https://www.chartjs.org) — bundled locally at assets/js/chart.umd.min.js (v4.5.0). Used to render the email-stats chart on the dashboard. Loaded entirely from your own server; no CDN call is made. Privacy Policy SendForce Mail Relay stores the following data in your WordPress database: Email logs (if logging is enabled): recipient email address, subject, headers, email body (optional), sent status, error messages, and timestamps. Email queue (if queue is enabled): same data as above, plus retry attempt count and next retry time. Plugin settings: your SMTP host, port, username, and encrypted password or API key. Email body logging can be disabled in Settings > Queue & Logging. Log entries are automatically deleted after the configured retention period (default: 30 days). All data is deleted when the plugin is uninstalled. We recommend adding a note to your site’s privacy policy if you log email content, informing users that outgoing email metadata may be stored.

Versatile plugin that lets you send email and SMS notifications to your users and that also integrates with WooCommerce and WPForms to offer enhanced notifications for those plugins, as well as being a full-featured SMTP and email logging solution. Key Features Send email messages to specific users, lists or all users. Trigger automatic email notifications based on specific actions or events. Trigger automatic SMS notifications based on specific actions or events. Trigger custom WooCommerce SMS or email notifications for specific actions, including a new purchaser, an abandoned cart, etc. Add SMS notifications to WPForms submissions. Full email logging, so you can keep track of sent emails and troubleshoot any sending issues. Add your SMTP info, so you can route emails via your real address/server and greatly reduce the chances of them getting blocked/marked as spam. Advanced Email Notifications With Ultimate WP Mail, you can quickly and easily create an unlimited number of customized email messages and templates, which you can send directly to registered users on your site. You can send one-time emails to specific users or create templates that you can use repeatedly, such as when creating custom send events (discussed below), and which can be sent to individual users, all users or to specific lists of users that you can put together in the plugin. With an easy-to-use visual designer, you can craft your email templates in no time. Or just use one of our included base templates! And, with the smart previewing features, you’ll be able to see what your email will look like before sending it. SMS Notifications (ultimate version feature) The ultimate version of the plugin also comes with the ability to send SMS notifications. These can be sent manually or automatically via triggers and send actions that you can create (more on that below). Imagine being able to text your customer with order details or site updates. A much more effective way to notify them. These can also be integrated with the available WooCommerce features (discussed below). By combining the SMS notifications with email notifications, you can greatly improve not only your ability to reach your users and customers in a timely manner, but also improve your CRM while automating the workflow on your end! WooCommerce Notifications Ultimate WP Mail comes with a suite of built-in WooCommerce integration features that give you the ability to send emails or SMS notifications to WooCommerce users on your site, including specific subsets of users (e.g. previous purchasers of a certain product), and also to create automatic WooCommerce email and WooCommerce SMS send triggers for specific actions (e.g. when someone has an abandoned cart, when a new product is added, etc.). WooCommerce notification features include: Send a custom SMS and/or email message to new and past purchasers of specific products or products within a specific category. Mix and match this with custom lists you’ve created for targeted WooCommerce emails. The perfect CRM for WooCommerce! Assign a specific email or SMS notification to send to users when a new product is added. Automatically notify users who have an abandoned cart, to help boost WooCommerce conversions. Send an automatic message a specific amount of time after a WooCommerce purchase (e.g. as a follow up or requesting a review, etc.) WPForms SMS Notifications (ultimate version feature) The ultimate version of the plugin also integrates directly with the WPForms plugin. Now, when you create a new form in WPForms, you can add SMS notification triggers, which allow you to send an SMS messages directly to people who fill out the form, so you can make sure they know their submission was received and provide them with any necessary info. You also have the ability to make the SMS notification dependent on a specific input value in the form, so you can keep your customers/users updated and provide them with real-time feedback. Not only is this helpful to reassure your users and keep them engaged, but it provides you with a new avenue for marketing and/or CRM, via a method the user is much more likely to view and actually read. This can all be set up directly in the WPForms plugin when creating your new form or modifying an existing one. We’ve built it as a new panel in the WPForms editor, so you can stick to the workflow you’re already used to and easily set up your SMS notifications. Automatic Send Events/Triggers Ultimate WP Mail comes with the ability to create send events. These are triggers that will automatically send out a notification (email and/or SMS) when something specific happens on your site. There are many available send events, including the WooCommerce features mentioned above as well as site-specific triggers like when a profile is updated, a password is changed, a new post is published, a new comment is created, and more. You can assign any email or SMS that you have created in the plugin to each send event. You could even create multiple send events for the same trigger and assign multiple different notifications to them. The possibilities are endless! Available send actions include: New user registration When a user profile is updated When a user role changes When a user password is reset After a specified amount of time that a user has not logged in When a new post is published When a there is a new comment A specified amount of time after a WooCommerce cart has been abandoned When a WooCommerce product is purchased A specified amount of time after a WooCommerce purchase When a new WooCommerce product is added When a WooCommerce subscription is purchased/created CRM Ultimate WP Mail is a great tool to strengthen your CRM (customer relationship management) toolset. Create an email list, email subscription or newsletter signup. Schedule emails to send at any time and then track the email statistics after it is sent. The included templates, as well as the email builder tool, create a responsive email that will look good when opened on any device Email Logging The Ultimate WP Mail plugin also includes a powerful email logging tool. This logs not only the emails sent by the plugin itself, but all emails sent out from your WordPress. This is invaluable for knowing whether or not your messages are getting through and, if not, why. The details included in the log are: Email status (e.g. success, failure, failure reason) Subject Recipient Send date Output of the email content We have also included an option to send a notification to the admin whenever the log detects that an email has failed to send. You can customize this message with your own content and dynamic template tags that will automatically include pertinent information about the failed email. SMTP We have also included the ability for you to add in your own SMTP information for email sending. With this you can send emails from your real email address/server/host. WordPress users often find that automatic emails sent from their site fail to get to the recipient. This is usually because they are blocked or flagged as spam. If you have checked the logs and noticed the emails are being sent, but not received, then it’s usually a good idea to use the SMTP feature to send emails via your real address. This will greatly reduce the chance of them getting blocked. The following SMTP info can be entered/customized: SMTP host Encryption type Port number Email address authentication You will also find options that let you specify the from name and address for your automatic emails. Subscription Interests The Ultimate WP Mail plugin also comes with the ability for you to let users choose different interests for which they can receive notification updates. This can be added to the user profile page and the user registration form. You can also add it anywhere else on your site using the handy included Subscription Interests Gutenberg block or shortcode. Here they can choose from the following interests: WooCommerce product categories Post categories Unique Ultimate WP Mail categories, which you can include in the plugin and utilize for custom emails If a user has selected any subscription interest, they will automatically receive a notification when that event happens (new product or post is published, etc.). Additional Features Ultimate WP Mail comes with a number of other advanced email sending features that will help you make your email management and email sending as efficient and effective as possible. Additional features include: User statistics that show the number of emails opened and links clicked Email categories, which can be used in combination with user lists to create well-targeted emails Option to automatically include an unsubscribe link in emails Styling options to further refine the look of your emails (email background color, email text alignment, email block styling) Labelling options, so you can change the text of elements like the subscribe and unsubscribe links as well as the subscription interests form The emails created in and by Ultimate WP Mail are all responsive emails. If you are looking for a tool that will help you send out mobile emails or help with your mobile CRM setup, this is it. A perfect complement to your current email marketing efforts, you can send a bulk email or mass email to any or all users. And, with the included newsletter signup email widget, you can get new users and email subscribers effortlessly. Set up WooCommerce reminders and WooCommerce notifications, as well as email reminders for other elements. Create notifications for specific actions and send emails directly to your users. With Ultimate WP Mail, the notification sending possibilities are endless. Hooks You can use the following filters and actions to add your own functions. Filters: – ewd_uwpm_title: Parameters are the email’s subject and the Params array for that email – ewd_uwpm_content_pre_substitutions: Parameters are the email’s content and the Params array for that email – ewd_uwpm_content_post_substitutions: Parameters are the email’s content and the Params array for that email – ewd_uwpm_headers: Parameters are the email’s headers array and the Params array for that email Actions: – ewd_uwpm_email_sent: Parameters are the Params array for that email and the email’s unique identifier, if the email was sent to a user – uwpm_register_custom_element: Used for registering custom email variables, post in the forum if you need help using it! – uwpm_register_custom_element_section: Used for registering sections for custom email variables For help and support FAQs The installation guide The Ultimate WP Mail support forum Our Support Center