asp.net mvc routing issue when run from within subfolder of web site root

Question

The following works great when I run my app in the web site root.

$("#randomQuote").load("<%: Url.Action("UpdateQuote", "Home") %>");  

where Home is my controller and UpdateQuote my action

However, when I run this as an application in a sub folder of my root web site, it doesn't. What am I missing? Here's my routing table:

routes.MapRoute(  
    "Action", 
    "{action}",  
    new { controller = "Home", action = "Home"});  

Thanks