I found this by accident and got most of it working (I think). I can go to the url on the server where I have it hosted and can get into it fine, however when I go to browse My Documents or any of the mapped drives - It says:
Error: Unauthorised Access You have attempted to access a restricted resource.
This is a permissions issue, either the user you have logged in with does not have access to the drives you have mapped or there is an issue with the AD bind user and it cannot read the groups that the user is a member of (i think)
I would check these first.
Also check that you have BASIC authentication enabled not anonymous or integrated - This will also cause an issue