Try in EPiServerFramework configuration section to use the virtualPathMappings element to override it instead. Make sure the VirtualPathMappedProvider is in the list as well.

<virtualPathMappings>
    <add url="util/logout.aspx" mappedUrl="/Accont/Logout" />
</virtualPathMappings>

Hope this helps

Frederik

Frederik thanks for your answer.

I've added this provider under virtualPathProviders

<add name="CustomUrlMapping" type="EPiServer.Web.Hosting.VirtualPathMappedProvider, EPiServer" />

then

<virtualPathMappings>
<add url="~/util/logout.aspx" mappedUrl="~/logout.aspx" />
</virtualPathMappings>

It seems to work only if the file extension is the same though.

Is there anything else I can override to use an MVC route?

Thanks.

For anyone else looking this would work:

public class Startup 
{
	public void Configuration(IAppBuilder app)
	{
		app.Map("/util/logout.aspx", map =>
		{
			map.Run(ctx =>
			{
				ctx.Response.Redirect("/to/custom/route");
				return Task.FromResult(0);
			});
		});
	}
}