FREE MODULE — COMMUNICATION
WordPress SMTP Email Delivery That Actually Works
Stop losing orders, password resets, and customer emails to spam. LuperIQ Email SMTP routes every WordPress email through a reliable connector — with full logging, retry logic, and analytics built in.
The Problem With WordPress Email Delivery
WordPress uses PHP's mail() function by default. Most web hosts either restrict it, deprioritize it, or send it straight to spam. The result: customers never get their order confirmations, password resets fail, and contact form submissions vanish silently. You find out when someone complains — or you never find out at all.
LuperIQ Email SMTP intercepts every single WordPress email before it leaves your server and routes it through a connector you control — whether that's your own SMTP server, the LuperIQ relay, or the default PHP mailer as a fallback. Every send is logged, every failure is retried, and every delivery is tracked.
Everything You Need for Reliable WordPress SMTP Email Delivery
Multi-Connector Routing
Choose Your Delivery Method
Route email through your own SMTP server, the LuperIQ API relay, or the default PHP mailer. Swap connectors in seconds without touching code.
Deep Email Interception
Catches Every WordPress Email
Hooks into WordPress at priority -999, before any other plugin can interfere. Every transactional email, WooCommerce notification, and form submission goes through one reliable pipeline.
Smart Retry Queue
Failures Recover Automatically
Failed emails enter an Action Scheduler queue with exponential backoff: immediate retry, then 60 seconds, 5 minutes, and 30 minutes. Up to four attempts before marking as failed.
Full Email Log
See Every Send
Every outgoing email is logged with status (sent, failed, or blocked), delivery connector, latency in milliseconds, sender, recipient, headers, and attachment count.
Email Blocking
Stop Unwanted Sends
Block emails by exact address or substring pattern. Blocked emails are logged separately (last 100 entries) so you can audit what was stopped and why.
Encrypted Credentials
SMTP Passwords Stored Safely
SMTP credentials are encrypted with libsodium before storage. The encryption key lives outside your database in a separate file at wp-content/luperiq_smtp.key.
Analytics Dashboard
Opens, Clicks, and Delivery Rates
Track total sends, unique opens, unique clicks, open rate, click rate, and CTOR with an hourly breakdown chart — all inside your WordPress admin.
Campaign Performance
Marketing vs. Transactional
See performance by subject line. Separate marketing emails from transactional sends so you can measure what actually moves the needle.
WP Mail SMTP Import
Migrate in One Click
Already using WP Mail SMTP? The module detects it automatically, shows a preview of your existing settings, and lets you import them with a single button.
Who This Module Is Built For
Any WordPress site that sends email and cares whether those emails actually arrive.
WooCommerce Store Owners
- Order confirmations, shipping notifications, and refund emails must land in the inbox — not spam.
- Abandoned cart recovery emails depend on reliable delivery to generate revenue.
- Customer account emails (password reset, registration) create support tickets when they fail.
Agencies Managing Client Sites
- One module covers all client email routing with per-site SMTP configuration.
- The full email log gives you visibility to troubleshoot delivery issues for any client.
- Blocking rules let you suppress test sends in staging environments without code changes.
Small Business Sites
- Contact form submissions are business leads — losing them to spam is losing revenue.
- Membership and booking confirmation emails need to reach customers reliably.
- Password reset emails that never arrive create login support requests and frustrate users.
How the Connector System Works
The module intercepts all outgoing WordPress email using the pre_wp_mail filter at priority -999 — earlier than any other plugin in the chain. When an email fires, the module routes it through whichever connector you have configured in Settings.
Three connectors are fully operational today: your own SMTP server (any provider), the LuperIQ API relay for hosted delivery, and the Default connector which falls back to PHP mail() when needed. The connector setting is stored in the database but can be overridden by an environment variable or PHP constant in wp-config.php — useful for agencies who want to enforce a specific connector per environment without allowing admin changes.
If a send fails, the email does not silently disappear. It enters the retry queue managed by Action Scheduler — the same battle-tested queue used by WooCommerce. Retry attempts use exponential backoff: the first retry is immediate, followed by 60 seconds, 5 minutes, and 30 minutes. After four attempts, the email is marked as failed and logged. You can see every step in the Email Log tab.
Three-Tier Configuration: Constants, Environment Variables, Database
Most SMTP plugins store credentials only in the database. That creates two problems: credentials are exposed to any admin-level user, and different environments (local, staging, production) end up sharing the same settings.
LuperIQ Email SMTP uses a three-tier hierarchy. PHP constants defined in wp-config.php take highest priority, followed by server environment variables, then database options. When a constant or environment variable is set, the corresponding field in the admin UI is displayed as read-only — so other admins can see the setting exists without being able to modify it. This gives agencies and developers full control over sensitive credentials without locking non-technical admins out of the interface.
When credentials are stored via the database, they are encrypted using libsodium (SODIUM_CRYPTO_SECRETBOX) before being written to the options table. The encryption key is stored in a separate file outside the WordPress database — at wp-content/luperiq_smtp.key — so a database dump alone is not enough to recover your SMTP password. An hourly cron checks encryption health and alerts you if the key file is missing or corrupted.
Email Analytics Built Into the Module
Most SMTP plugins stop at delivery. LuperIQ Email SMTP goes further: the Analytics tab shows you what happened after the email landed. Total sends, unique opens, unique clicks, open rate, click rate, and click-to-open rate (CTOR) are all tracked. An hourly breakdown chart shows you when email activity peaks throughout the day.
The Campaigns tab breaks performance down by subject line, so you can compare transactional messages against marketing sends. The Recipients tab shows your top recipients by volume and your top engagers by open and click activity. Click events capture IP address (with Cloudflare header awareness), user agent, and session ID — giving you enough data to understand engagement without requiring a separate analytics platform.
What You Get: Eight Admin Tabs, One Module
Settings
Configure your active delivery connector, SMTP credentials, and three-tier config overrides.
Blocking
Add block rules by exact address or pattern. Review the last 100 blocked send attempts.
Test
Send a test email from the admin to verify your connector is working before going live.
Email Log
Full send history with status, connector, latency, headers, and attachment count per message.
System Logs
Module-level system events and error messages for troubleshooting connector issues.
Analytics
Opens, clicks, CTOR, and hourly send volume across your entire email program.
Campaigns
Performance by subject line with marketing vs. transactional separation.
Recipients
Top recipients by volume and top engagers by open and click activity.
Frequently Asked Questions
Does this replace WP Mail SMTP?
It is a direct alternative. If you are already running WP Mail SMTP, the module detects it automatically and offers a one-click import with a settings preview before anything is changed. You can then deactivate WP Mail SMTP.
Which SMTP providers can I use?
Any SMTP server works — Gmail, Outlook, Amazon SES, Postmark, your own mail server, or any provider that offers SMTP credentials. You supply the host, port, username, and password in Settings.
What happens if an email fails to send?
The email enters the Action Scheduler retry queue with exponential backoff: immediate retry, 60 seconds, 5 minutes, and 30 minutes. After four attempts the email is marked as failed in the Email Log. No email disappears silently.
How are SMTP credentials protected?
Credentials stored via the database are encrypted with libsodium before being written to the options table. The encryption key lives in a separate file at wp-content/luperiq_smtp.key outside the database. An hourly health check verifies the key file is intact.
Can I block specific email addresses from receiving WordPress emails?
Yes. The Blocking tab lets you add rules by exact address or substring pattern. Blocked emails are logged separately so you can audit what was stopped and when.
Is the Email SMTP module free?
Yes, it is included in the free tier. No paid plan is required to configure a connector, view the email log, or use the blocking and retry features.
Fix WordPress Email Delivery Today — Free
Install LuperIQ, activate the Email SMTP module, and connect your SMTP server in minutes. Full email logging, retry queues, and analytics are included at no cost.