In a domain environment.
My environment is seeing a spike in an issue where users cannot log into their profiles, while being met with error: "The User Profile service failed the logon. User profile cannot be loaded."
After this the user, after entering correct password, will have a profile that will not load.
Also, Windows will not create new profiles and will spit out the same error at log on screen.
However, local admin account and profile will work.
After looking online I found suggested registry fixes. But these did not work for me. The only fix that would work for me is creating a new default folder under c:\users and copying over a working good ntuser.dat file from another default folder on another good machine.
I have a fix already in place (by rebuilding default profile with good ntuser.dat file) but these issues are popping up more and more frequently, so I'm trying to find out what is causing this corruption of the default folder and/or its ntuser.dat file.
I have an suspicion that it could be the permissions of the default folder being set to non-readable for user accounts that attempt to log on but why would this matter if the profile is already created? Regardless, perhaps something is forcing these permissions to be non-readable? I need more computers to test this theory.
So I'm trying to narrow it down and see if it's the ntuser.dat file becoming corrupted in default folder or the permissions of default folder are being changed to non-readable for user accounts.
Your thoughts? Any ideas on what could be causing a sudden occurrence of this issue? I know there are a lot of articles on how to fix this issue but I'd like to know what is causing it. In my environment it's not just a one-off thing--it's happening with increasing frequency which makes me believe there is something else in the environment that is causing it. Could it be windows updates?