This note applies to an FDCC-hardened instance of Windows Vista.

It seems that Vista requires elevated permissions in order to process a domain logon for the first time. If the user account in question is not a local Administrator on the box, the following error message is generated: "The User Profile Service service failed the logon. User Profile cannot be loaded."

The fun part is that Administrative rights may be withdrawn once the user profile is created for the first time. The issue here seems to be that Everyone does not have write privs on the C:\Users folder, which keeps the initial profile folder from being created.

So perhaps this is an example of over-zealous system hardening, but it's DEFINITELY another impressive example of a completely unhelpful Microsoft error message.