Esri Roads and Highways for Server system requirements
Esri Roads and Highways for Server requires ArcGIS for Server. ArcGIS for Server must be installed with .NET Extension Support enabled. If you installed ArcGIS for Server without .NET Extension support, you must install the correct Microsoft .NET Framework version and enable it by modifying your ArcGIS for Server installation.
System requirements for Esri Roads and Highways for Server match those of ArcGIS for Server.