Configure Postmark in FluentSMTP

In Postmark

1. Sign in at account.postmarkapp.com.
2. Open the Server you send transactional mail from (not the account-wide token unless you know you want that).
3. API Tokens tab. Copy a server token.
4. Confirm the From domain (or sender signature) is verified.
5. Note the Message Stream ID. Default is outbound.

The plugin points at Postmark servers.

In FluentSMTP

Settings → FluentSMTP, pick Postmark.

• From Email on a verified signature / domain.
• API Key: the server token.
• Message Stream: usually outbound. Use another stream if you created one on purpose.
• Track Opens and Track Links: optional. HTML only. They add Postmark tracking.

Leave Store in Database selected. You can tick Disable Encryption, or switch to Store in wp-config.php. Both are optional. See Where secrets are stored.

Save Connection Settings, send a test.