I cam across this today and it bugged the hell out of me. I am using a custom ControllerFactory (kindly provided by Steve Sanderson’s awesome Pro ASP.NET MVC Framework) set in the global.asax.cs as such:

protected void Application_Start() 
{ 
    RegisterRoutes(RouteTable.Routes); 

    // Configure log4net 
    log4net.Config.XmlConfigurator.Configure(); 

    // Configure CastleWindsor 
    ControllerBuilder
        .Current
        .SetControllerFactory(new WindsorControllerFactory()); 
}

During the upgrade this stopped working and i started getting the following error:

System.MissingMethodException: No parameterless constructor defined for this object

I tracked the error down to the fact the constructors in my Controllers were not being initialized and I found the following quote from the breaking changes section of the What’s New in ASP.NET MVC 2:

“Custom controller factories are often used to provide dependency injection for ASP.NET MVC applications. To update the custom controller factories to support ASP.NET MVC 2, change the method signature or signatures to match the new signatures, and use the request context parameter instead of the property.”

After a little digging, the only change I needed to make was altering my custom ControllerFactory’s GetControllerInstance() override from:

protected override IController GetControllerInstance(Type controllerType) 
{ 
    return (IController)_container.Resolve(controllerType); 
}

to

protected override IController GetControllerInstance(RequestContext requestContext, Type controllerType) 
{ 
    return (IController)_container.Resolve(controllerType); 
}