Configure SMTP separately
Use an already working SendGrid SMTP transport that preserves the message’s X-SMTPAPI unique argument. In Settings → Delivery and site safety → Provider feedback and throughput, selecting SendGrid does not configure SMTP or store its credentials. Other providers and mail API integrations are not qualified by this connector.
Enable signed events at both ends
Your public site must use HTTPS. Follow SendGrid’s signed Event Webhook setup, select Bounce and Spam Reports, and use the Signed Event Webhook URL shown by the plugin. Paste the provider’s P-256 public verification key into the matching field, not an API key. Enable verified feedback only after setup.
Verify the actual connection using your provider and an owned test address. Local tests of signature handling do not establish that your SendGrid account, SMTP headers or webhook delivery are configured correctly.
Understand what changes a contact
Only a valid, correlated, same-address permanent bounce or spam complaint suppresses future mail. Temporary blocks and unmatched events do not. Signatures, timestamps and message correlation are checked before a contact can be affected. Open and engagement events are ignored by this connector.
Receiving-server acceptance is distinct from inbox placement. Optional click reporting is a separate feature and is not supplied by this feedback connector.
Keep suppression and retention intact
Disabling the connector, resetting a contact status or importing the address again does not remove a provider suppression. There is no quick unsuppress button. Correlations and feedback receipts are kept for 90 days; keyed suppression remains until explicit plugin-data deletion.
Inspect the panel’s recent verified and unmatched counts, then diagnose provider configuration if events cannot correlate. Do not erase suppression history just to make a list appear eligible.