Issue: You need to encrypt traffic with SSL by utilizing a cert from a recognized third party certificate authority and you’d like to do it ‘on the cheap’.
Solution: Your first step in obtaining an SSL cert is to purchase a “certificate credit”. Below is a list of the cheap SSL certificate products that I have had a positive experience implementing as well as details on the best type of certificate to choose for your situation.
Uber-Cheapest (but reputable) SSL cert resellers:
is my ‘go-to’ reseller when I need a BIG discount on Comodo or GeoTrust SSL Certificates. Using name brand certs instills user confidence and browser compatibility.
Namecheap, is as the name implies, really cheap with certs starting at $9.00 for a “single-domain” Comodo PositiveSSL certificate.
Which of NameCheap’s Comodo SSL certificates should I choose?
If you are running Exchange 2007, 2010 or 2013 you will choose the Comodo PositiveSSL Multi-Domain (UCC) Certificate or the Comodo PositiveSSL Wildcard Certificate (if your AD domain name is identical to your internet domain name then you can use a Wildcard cert). If you are running Exchange 2003 or are installing the cert on a web server like IIS then you can generally go with the $9.00 ‘single-domain’ Comodo PositiveSSL certificate. Now it should be crystal clear whether you need a single domain, multi-domain (UCC), or wildcard certificate.
Once you purchase a certificate credit (above), use the following instructions to create a cert request (CSR) to submit to your Certificate Authority.
How to prepare a certificate request on Exchange 2016
How to prepare a certificate request on Exchange 2013
How to prepare a certificate request on Windows 2008 R2 / IIS 7.5
How to prepare a certificate request on Exchange 2003 / Windows 2003 / IIS 6