Launch Server Manager. Select Manage -> Add Roles and Features. Click Next. Select Role Based or Feature Based installation and hit next. Select the desired server from the server pool and hit next. Expand Web Server (IIS) -> Web Server -> Application Development and check ASP.NET 4.6. You may be prompted to add other dependencies such as .NET Extensibility framework 4.6 and CGI, ensure this prompt is accepted. Expand Web Server (IIS) -> Management Tools. Here ensure IIS management console and IIS management scripts and tools are selected. Click Next. Click Next again. Confirm the changes being made and then select Install to begin the IIS configuration. Once complete hit finish.

Open Internet Information Services (IIS) Manager. Right click on Application Pools from the tree view and choose Add Application Pool. Name the new application pool SmarterMail. Set the .Net Framework Version to v4.5.x. Set the Application Pools Managed Pipeline to 'Integrated'. Make sure "Start application pool immediately" is checked. Click OK

Open Internet Information Services (IIS) Manager. Click on your Server Name, and on the right side, under IIS, double-click ISAPI and CGI Restrictions. Verify that ASP.NET v4.5 is allowed. If not, right click on ASP.NET v4.5.x and select Allowed. On the left side of the page, right click on Sites in the tree view and choose Add Website.Name the site SmarterMail.If you created an Application Pool name other than SmarterMail, click Select and choose the correct Application Pool.For the physical path, browse to the SmarterMail -> MRS folder. The default location is C:\Program Files (x86)\SmarterTools\SmarterMail\MRS. For Binding, choose an IP address to use for Webmail. If this IP address is shared with another Web site, you will need to use a different port or Host Headers. Make sure "Start Web site immediately" is checked. Click OK

In IIS Manager, click on your ServerName.Under IIS, double click ISAPI and CGI Restrictions. Verify that ASP .NET v4.5 is allowed. If it is not, right-click on ASP .NET v4.5 and select Allowed. Right click on the SmarterMail application pool and select Advanced Settings. Under the Process Model heading, ensure the the Identity is set to the NetworkService account. Under the Recycling section, adjust the idle time out to 0 to ensure the web interface does not get shut down due to idle activity. Click OK. Open the Windows Services area and verify that the World Wide Publishing Service is running. Ensure the 'NetworkService' account has full control over the SmarterMail MRS directory.