When installing Exchange on a server for the first time, there are OS prerequisites that you need to install before you can move forward with the Exchange setup. Of course you can install them one at a time through the server manager or you can use PowerShell and run one command to solve all your problems and save a little time. I’m going to assume that you are installing all the standard Exchange roles on one Windows 2012 server. Microsoft recommends keeping all the roles together and not splitting them out to separate servers.
[PS] C:\Windows\system32> Import-Module ServerManager
[PS] C:\Windows\system32> Add-WindowsFeature NET-Framework-Features,NET-HTTP-Activation,RPC-over-HTTP-proxy,RSAT-Clustering,Web-Mgmt-Console,WAS-Process-Model,Web-Asp-Net,Web-Basic-Auth,Web-Client-Auth,Web-Digest-Auth,Web-Dir-Browsing,Web-Dyn-Compression,Web-Http-Errors,Web-Http-Logging,Web-Http-Redirect,Web-Http-Tracing,Web-ISAPI-Ext,Web-ISAPI-Filter,Web-Lgcy-Mgmt-Console,Web-Metabase,Web-Net-Ext,Web-Request-Monitor,Web-Server,Web-Static-Content,Web-Windows-Auth,Web-WMI -Restart
The above command installs all the needed OS prerequisites to run Exchange CAS, Hub Transport, and Mailbox roles on one Server running Windows 2012. You can get a detailed list of Exchange 2010 prerequisites broken out by OS version here.
This is just a little tip to try and help you save some time while setting up your Exchange 2010 environment.