Can the ActiveRoles Server service be installed on Windows 2008 / 2012 Server Core?
The ActiveRoles Server Services cannot be installed on the Windows 2008 / 2012 Server Core.
ActiveRoles Server installation components require .NET Framework to be installed as its prerequisite. Microsoft .NET Framework is not available on Server Core installations.
ActiveRoles Server also requires ADSI Provider but as Internet Explorer is not available on Server Core installations, this package can not be installed.
This also applicable to the ActiveRoles Server Web Interface (WI) installation on Windows 2008 and 2012 Server Core.
Refer to Microsoft Technet article - IIS 7.0 on Windows Server Core Installations: