Test Email Not Sending

Use this workflow when Send test mail fails.

Check the UI error

Copy the visible error text into your incident notes, but remove secrets.

Check sender setup

• Sender domain verifies.
• From address exists or is allowed.
• Display name and subject are filled.
• Template is selected.
• Recipient email is valid.

Check recipient eligibility

• Recipient is not unsubscribed.
• Recipient is not in the suspend list.
• Recipient domain has MX records.

Check delivery engine

For Local Postfix:

• Local queue service is healthy.
• Outbound mail is allowed by the provider.
• PTR/rDNS exists.

For KumoMTA or Tenant default:

• KumoMTA integration is enabled.
• Campaign sending or Send API is enabled for the relevant path.
• Sending profile is ready.
• Connection test passes.
• KumoMTA logs show injection.

If PING8 fails before injection

The issue is usually sender, recipient, quota, tenant status, or profile configuration.

If injection succeeds but no delivery appears

Check queue, provider response, and webhook lifecycle events.