SMTPDIAG

SMTPDIAG is an utility from Microsoft that is a diagnostic tool to determine if Simple Mail Transfer Protocol (SMTP) and Domain Name System (DNS) are configured correctly to deliver mail to an external e-mail address.  The application can be downloaded at:

http://www.microsoft.com/en-us/download/details.aspx?id=11393

The syntax for the application is:

SMTPDIAG "sender address" "recipient address" [-d target DNS] [/v]

smtpdiag_1

Below is an example of the –d switch to specify a DNS server to use, as well as the /v switch to include more details.

smtpdiag_2

The following error may be returned when the server is not an Exchange server and is not a member of an Active Directory domain.

smtpdiag_3