Question

I’m using VS 2010 with ASP.net MVC 2.

I recieved a program that was completed and when I was debugging the program I recieve an error message.

“Error 4 The type ‘System.Web.Routing.RouteTable’ exists in both ‘C:\Program Files\Reference Assemblies\Microsoft\Framework.NETFramework\v4.0\System.Web.dll’ and ‘C:\Documents and Settings\Vincent\Desktop\3\Manning.ASP.NET.MVC.2.in.Action.Jun.2010\aspnetmvc2inaction_code\lib\AspNetMvc\System.Web.Routing.dll’ C:\Documents and Settings\Vincent\Desktop\3\Manning.ASP.NET.MVC.2.in.Action.Jun.2010\aspnetmvc2inaction_code\src\Chapter01\GuestBook\Global.asax.cs”

and

“Error 1 The type ‘System.Web.Routing.RequestContext’ exists in both ‘c:\Program Files\Reference Assemblies\Microsoft\Framework.NETFramework\v4.0\System.Web.dll’ and ‘c:\Documents and Settings\Vincent\Desktop\3\Manning.ASP.NET.MVC.2.in.Action.Jun.2010\aspnetmvc2inaction_code\lib\AspNetMvc\System.Web.Routing.dll’ C:\Documents and Settings\Vincent\Desktop\3\Manning.ASP.NET.MVC.2.in.Action.Jun.2010\aspnetmvc2inaction_code\src\Chapter01\GuestBook\Controllers\AccountController.cs”.

The program was converted into VS 2010 format.

What should I do?

// Fullmetalboy

Answer 1

When you convert a project from .Net 2.0/3.5 to 4.0 in VS2010 the web projects will prompt you to upgrade the framework to 4.0 but you will need to manually go into the project properties and upgrade class library projects and certain other projects manually in the project properties. So this type of error is probably caused by your web project referencing the 4.0 version of System.Web.Routing but a class library in your solution is still referencing the 3.5 version.