1) Login into the server.
2) Create a New Website from IIS named as SmarterMail and apply below mentioned details:
-> Description: SmarterMail
-> IP Address: the primary IP address for your server
-> Host header for this Web site: mail.domainname.com
-> Path: C:\Proram Files\SmarterTools\SmarterMail\MRS
-> Website Permissions: check Read and Run scripts
3) Right Click on website and select properties.
4) On the ASP.NET tab, select the appropriate version of ASP.NET based on the version of SmarterMail.
5) On the HTTP Headers tab, click MIME Types -> Click New.
6) Enter the requested information:
-> Extension: .js
7) Click on Ok.
8) Create an A record in DNS for mail.domainname.com that points to the primary IP address for your server