SMTP Diagnostics 1.0

Windows This is a Community Contributed Download

Supported byEmail, Phone, Knowledge base, Forums
Works WithIIS 5, IIS 5.1, IIS 6
Documentation N/A
Updated onMarch 19, 2010
Uploaded byMicrosoft


SMTPDiag is a troubleshooting tool designed to work directly on a Windows server with IIS/SMTP service enabled or with Exchange Server installed. It utilizes the same APIs as Windows and Exchange in order to diagnose configuration and connection issues involving SMTP and DNS.


SMTPDiag 1.0 aims at helping simplifying troubleshooting for failures occurring because of DNS or SMTP configuration problems.  SMTPDiag uses the following features to isolate and determine problems:

  • Makes test requests based on user-inputted information such as sender & receiver
  • Validates that DNS MX records are configured correctly
  • Ensures that the correct Firewall or Proxy ports are open for SMTP to properly work
  • Ensures the correct permissions on the relevant SMTP directories such as BadMail, Pickup, etc. 


Written by the Microsoft Exchange team, SMTPDiag is a beneficial tool for anyone using SMTP in their Windows-based environment.  It is simple to use and run and has excellent analysis engine.


SMTPDiag works on any 32-bit version of Windows including the following operating systems:

NOTE:  The installation of this tool does not require the installation of the W3SVC service

  • Windows NT 4.0
  • Windows 2000 Server
  • Windows Server 2003
  • Windows Server 2003 R2