Troubleshoot Email Authentication and Deliverability
Diagnose SMTP/API authentication, sender verification, DNS, spam placement, bounces, replies and unsubscribe problems.
Overview
Search Aliases: email not sending, email spam, SMTP error, DKIM error, email reply missing
TROUBLESHOOTING METHOD
- Record workspace, sender, time in PKT and provider error.
- Send to an internal test address.
- Check connection status.
- Check sender/domain verification.
- Check SMTP/API/OAuth credential.
- Check SPF, DKIM and DMARC.
- Check provider limit and account status.
- Check audience, content and links.
- Check bounce, complaint and suppression events.
- Capture redacted evidence.
COMMON ISSUES & SOLUTIONS
| Authentication failed | Host, port, username, app password/API key, OAuth and encryption. |
|---|---|
| Sender not allowed | Complete provider verification. |
| Email goes to spam | Review authentication, reputation, list quality, subject, content and complaint rate. |
| Hard bounce | Remove or correct invalid address. |
| Soft bounce | Review temporary recipient/provider issue and retry policy. |
| Reply not connected | Review Reply-To and inbound mailbox connection. |
| Unsubscribe ignored | Review campaign audience refresh and suppression. |
| App password stopped after Google password change | Generate a replacement if the organization permits app passwords. |
SAFE SUPPORT REQUEST
Include sender shown partially, connection type, provider error, time in PKT and redacted authentication result. Never include a password, app password, API key, DNS-management login or customer list.
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