Is IIS 7.5 required for ASP.NET MVC 5.1, ASP.NET Web API 2.1?

Question

After upgrading the project to WebApi 2.1 and MVC 5.1 getting following errors on IIS7:

This operation requires IIS version 7.5 or higher running in integrated pipeline mode.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.PlatformNotSupportedException: This operation requires IIS version 7.5 or higher running in integrated pipeline mode.

Source Error: An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace: [PlatformNotSupportedException: This operation requires IIS version 7.5 or higher running in integrated pipeline mode.] System.Web.HttpResponse.get_ClientDisconnectedToken() +3127102
System.Web.HttpResponseWrapper.get_ClientDisconnectedToken() +9
System.Web.Http.WebHost.HttpResponseBaseExtensions.GetClientDisconnectedTokenWhenFixed(HttpResponseBase response) +58
System.Web.Http.WebHost.d__0.MoveNext() +134 System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +93
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +52 System.Web.TaskAsyncHelper.EndTask(IAsyncResult ar) +60
System.Web.HttpTaskAsyncHandler.System.Web.IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) +6
System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +9514812 System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +155

______________________ Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.18408

Answer 1

This was a regression from Web API 2 to 2.1. Following bug is keeping tracking of this:

https://aspnetwebstack.codeplex.com/workitem/1645

NOTE: The fix has been released today (2/10/2014). Make sure to update your packages.