How to Configure Windows SMTP Server to Support TLS Connection Share on Facebook Tweet on Twitter Share on LinkedIn Home › Forums › Messaging Software › Exchange 2007 / 2010 / 2013 › How to Configure Windows SMTP Server to Support TLS Connection This topic contains 0 replies, has 1 voice, and was last updated by slapbunny 2 years, 7 months ago. Viewing 1 post (of 1 total) Author Posts slapbunnyMember August 4, 2016 at 4:31 pm #166529 Hello I am new to certificates and I am running into a problem. We have been asked by some of our customers to implement TLS on our email communications. Our Setup: Server 1: Microsoft Server 2003 Enterprise (IIS 6) Role: SMTP Gateway/Mail Relay Server Spam Server (GFI Mailessentials) This server acts as a smart host to filter out spam and forward email to our Exchange Server. Server 2: Microsoft Server 2012 / Exchange 2010 I have performed the Exchange Certificate on the Exchange Server. Purchased, installed the certificates and assigned the services. When I Telnet the localhost 25 on the Exchange Server, I am getting the 250-STARTTLS on the EHLO command. It seems everything is fine on the Exchange side. The SMTP Server is no giving this option. How do I get the SMTP Relay Server to negotiate TLS. Do I need to upgrade to a newer Server OS? Do I need to install certificates on the SMTP server? If so can I use the same certificates that I have purchased? Any help would be much appreciated Thanks Author Posts Viewing 1 post (of 1 total) You must be logged in to reply to this topic.