The message "The User Profile Service service failed the sign-in. User profile cannot be loaded." is displayed when logging in.
This issue can be caused by a corrupted Default profile in C:\Users\
To resolve:
Login with a domain / local administrative account
Open RegEdit and review HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList for any profiles with a .bak extension
Rename C:\Users\Default to Default.old
Copy C:\Users\Default from a working machine at the same OS level
Log out and log in as the first user to test
Remove Default.old
