OptiPub protects your sender reputation by checking email addresses before (and after) they join your list. There are two complementary verification paths that you control from the same settings page:

Navigate to Settings → Email Verification

These paths work together. EVP is an optional shortcut for subscribe forms when the browser and mailbox provider support it. Traditional automatic verification remains the default path for every other case (unsupported browsers, no confirmation available, API signups, segment verifies, and any EVP attempt that does not succeed).

flowchart TD
    A[Subscribe form submission] --> B{EVP enabled and confirmation present?}
    B -->|Yes, confirmation valid| C[Treat as verified — skip traditional check]
    B -->|No or confirmation unavailable| D{Automatic verification enabled?}
    D -->|Yes| E[Traditional verification check]
    D -->|No| F[Accept without verification scan]
    E --> G{Safe to send?}
    G -->|Yes| H[Active subscription]
    G -->|No| I[Lead / marked invalid or trap]
    C --> H

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Automatic Email Verification

Automatic email verification scans addresses through OptiPub's verification service so risky or undeliverable emails are caught before they damage deliverability.

Enable Automatic Email Verification

Toggle Enable automatic email verification on to run a verification check when:

• A visitor signs up through an OptiPub subscribe form or related signup API (and EVP did not already confirm the address)
• You run Verify on a segment

We recommend leaving automatic verification on. Disabling it can allow invalid, trap, and otherwise risky emails onto your list and hurt sender reputation.

When verification is enabled and a check fails, OptiPub marks the email invalid (invalid reason: Email Verification) and the signup is typically stored as a lead rather than a full active subscription. See Segmenting for Invalid and Temp Invalid Subscribers for how invalid status affects delivery and segmentation.

Mark Verification Traps as Invalid

When automatic verification is on, Mark verification traps as invalid controls how trap / high-risk flags from the verification service are treated:

We recommend keeping this setting enabled.

Email Reverification Period

Verification results are cached against the address for a period you choose. Addresses verified within that window are not charged again and are not re-scanned unless you force a verify.

We recommend 30 days.

Mark Spam Complainants Globally Invalid

Mark spam complainants globally invalid is separate from the signup scan. It controls what happens when OptiPub receives a spam complaint (FBL):

Use Off only if complaints should stay scoped to the publication that received them.

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Email Verification Protocol (EVP)

EVP lets a supported browser ask the subscriber's mailbox provider to confirm that the person controls the address they are entering on your subscribe form. When that confirmation succeeds, OptiPub treats the address as verified for that signup and skips the traditional (paid) verification check.

Enable EVP

1. Open Settings → Email Verification.
2. Turn on Enable Email Verification Protocol (EVP).
3. Save your settings.

EVP is off by default. Turning it on only affects OptiPub subscribe forms (optipub-subscribe). It does not replace automatic verification for segment verifies, imports, or other signup paths.

How Signup Behaves With EVP On

1. The visitor focuses the email field on your subscribe form.
2. If their browser and mailbox provider support confirmation, the browser can attach a confirmation to the submission.
3. OptiPub validates that confirmation.
4. On success — the address is treated as verified for that signup; traditional verification is skipped.
5. Otherwise — signup continues with your normal automatic verification settings (or without a scan if automatic verification is disabled).

EVP never blocks a signup by itself. If confirmation is missing or cannot be validated, OptiPub falls through to traditional verification (or accepts the address if automatic verification is off).

What EVP Does Not Cover

• Visitors on browsers or mailbox providers that do not support confirmation
• Custom forms that are not optipub-subscribe
• Segment Verify, imports, and other non-form entry points
• Guaranteeing confirmation on every signup — support is still rolling out across the industry

Keep Enable automatic email verification on so those cases stay protected.

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Related Guides

• Segmenting for Invalid and Temp Invalid Subscribers — how invalid / trap status affects delivery and segments
• optipub-subscribe — embedding subscribe forms on your site
• Bot Protection — stopping automated signups (separate from verifying the email address itself)
• Segments — including the Verify action on a segment