RemoteApp giving 'access is denied'

Hello,

I've setup a RemoteApp (calculator) for testing purposes and when I try to access it through the browser I get 'Access is Denied'.

I'm on a domain controller with an administrator privileges. I added my username to the Remote Desktop Users group and TS Web Access group and a bunch of other groups too. I also disabled the 'allow single logon to terminal' in the policy settings but still I'm getting access is denied.

I'm on a windows server 2008 r2

What must I do to get this working?