Ok, mojoportal needs to be either a root web site or defined as an application in a 1 level deep folder so the url used can be like http://localhost/ or http://localhost/somefolder but not like http://localhost/folder1/folder2/
If you have other .NET code in the www folder there can also be conflicts with the web.config settings like that machine to application error.
So I recommend change your alias to make sure mojoportal either runs at the root or one level deep, if running it 1 level deep you may need to try removing any other web.config file that lives in the root folder ie www in your example.
Hope it helps,
Joe