I didn't know it existed until I was looking on the ImageResizer website, but the /resizer.debug.ashx page says:

(Critical): The MvcRoutingShim plugin must be installed if you are using MVC or System.Web.Routing System.Web.Routing is loaded. You must install the MvcRoutingShim plugin. Add ImageResizer.Mvc.dll to your project, and add '' to the

I am developing using Visual Studio but not with MVC. It all seems to work OK, but should I install the above plugin anyway?!