SMTP Debug Tool

T he SMTP Debug Tool is designed to simplify email troubleshooting, and is presented as a no-cost service designed to help test and validate an SMTP setup. SMTP Debug is a 3-in-1 Tool for diagnosing and resolving SMTP.

SMTP Test
Produces a quick log of an SMTP session and verifies settings in under 5 minutes. No registration required—accessible from a browser.

SMTP Proxy
Runs and logs an existing SMTP connection between an app and mail provider. Identifies errors in an SMTP session in 15 minutes or less.

SMTP Blackhole
Debugs email-sending systems (CMS, CRM, apps) safely. Uses test credentials to simulate SMTP sessions, review logs, and troubleshoot without exposing sensitive data.

The tool is presented as ideal for resolving issues with providers like Amazon SES, SMTP2GO, UniOne or Mailgun, the tool allows users to verify a connection by sending a test email and generating a full log of the server communication. Users can then review the log to identify and address any errors or anomalies in the sending process.