Update: I can confirm that this issue is fixed in Visual Studio with Update 1.
I recently ran into an issue where after pushing out new Visual Studio 2015 installs (with SCCM), new users could not log into those machines. When trying to log in with a new user, the following error occurs: “The User Profile Service failed the logon. User profile cannot be loaded.”
When looking at the Event Logs, I saw access denied errors related to failing to copy some files to the users new profile from C:\Users\Default. (This hidden default profile is what all new user profiles are based from.)