I added a simple test default.aspx page and got an exception that seems to indicate that ASP.NET MVC 6 only runs under IIS 7.5 and later. In terms of system requirements that translates to Windows Server 2008 R2 and later, at least at the time of writing this:
Exception information:
Exception type: PlatformNotSupportedException
Exception message: IIS 7.5 or higher is required.
at AspNet.Loader.Error.Bootstrapper_RequiresIIS75()
at AspNet.Loader.Bootstrapper.LoadApplicationNet45(String appId, String appConfigPath, IProcessHostSupportFunctions supportFunctions, LoadApplicationData* pLoadAppData, Int32 loadAppDataSize, String runtimePackagePath, String appBasePath)
at AspNet.Loader.Bootstrapper.LoadApplication(String appId, String appConfigPath, IProcessHostSupportFunctions supportFunctions, LoadApplicationData* pLoadAppData, Int32 loadAppDataSize)
at System.Runtime.InteropServices.Marshal.ThrowExceptionForHRInternal(Int32 errorCode, IntPtr errorInfo)
at System.Web.Hosting.ProcessHost.System.Web.Hosting.IProcessHostLite.ReportCustomLoaderError(String appId, Int32 hr, AppDomain newlyCreatedAppDomain)
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at System.Web.Hosting.ApplicationManager.CreateAppDomainWithHostingEnvironment(String appId, IApplicationHost appHost, HostingEnvironmentParameters hostingParameters) at System.Web.HttpRuntime.HostingInit(HostingEnvironmentFlags hostingFlags, PolicyLevel policyLevel, Exception appDomainCreationException)