Page Last Updated: 01/02/2010
MX Record and Telnet Worked Example

This is an example of using multiple command line tools to verify information about an email server. This is old information for microsoft.com, but the procedure still applies.

First, get the MX record information.

C:\>nslookup
Default Server:  server.domain.co.uk
Address:  192.168.1.1

> set type=mx
> microsoft.com
Server:  server.domain.co.uk
Address:  192.168.1.1

Non-authoritative answer:

microsoft.com   MX preference = 10, mail exchanger = mailc.microsoft.com
microsoft.com   MX preference = 10, mail exchanger = maila.microsoft.com
microsoft.com   MX preference = 10, mail exchanger = mailb.microsoft.com

maila.microsoft.com     internet address = 131.107.1.7
maila.microsoft.com     internet address = 131.107.1.6
mailb.microsoft.com     internet address = 131.107.3.123
mailb.microsoft.com     internet address = 205.248.102.77
mailc.microsoft.com     internet address = 205.248.102.78
mailc.microsoft.com     internet address = 205.248.102.79
>
 

When you have the MX server information, see if you can telnet to port 25 of the remote server. As you can - each server has multiple IP addresses.

For example (using the above information)

telnet maila.microsoft.com 25

You should then get a banner similar to this:

220 mail04.microsoft.com Microsoft ESMTP MAIL Service ready at Thu, 7 Jan 2010 05:57:59 -0800

About this site

Most of this information originally started life as a page on amset.info, our community assistance site. However that site is targeted at Microsoft Exchange server, as Sembee Ltd. is a Microsoft Exchange consultancy. Therefore it was moved to its own domain in early 2010. Traffic from amset.info is directed here.

Other sites that are owned and operated by Sembee Ltd include kbsearch.info, certificatesforexchange.com, loginscripts.info, office-recovery.info, wuauclt.info, blog.sembee.co.uk, exbpa.com and amset.info.