We help IT Professionals succeed at work.

TLS on Exchange 2003

jcorsoomni asked

Could someone please provide me with instructions for setting up SMTP communication over TLS with an outside organziation?
Watch Question

Maen Abu-TabanjehNetwork Administrator, Network Consultant
Top Expert 2011
Gary ColtharpSr. Systems Engineer

You need to have a working certificate installed...as does the remote organization. Self signed can be used if you install the remote org's certificate.

next on your receive and send connectors, you enable TLS (if not already). Don't shut off the others unless you are setting this up with an email filtering host that you only want to send/receive from them.
I would add that to check if it is working you should enable the SMTP logging inside of Exchange.  Example, on the SMTP Virtual Default service enable the logging checkbox (and click the button to see more options, add more logging items if you want).
Then in the SMTP log you should see STARTTLS in the smtp log.  
This article also has some info at the bottom to check that your server will accept TLS