When you log on to your Windows profile, all your profile’s information and settings are gone away. Corruption of a single file can unable the windows from accessing it and it will log you on to a temporary profile which you can use, during in a temporary profile any changes you make to this temporary profile will not be saved and it will be a fresh each time you log in.
Cause of corruption can be a recently installed update or a software or incorrectly shutting your computer down for that matter. You can try to restart your computer 3 to 4 times (that has worked for some users) otherwise you can following the solutions below.
Login to another account with Admin Rights then go to Regedit then point to this key:
In the left pane, double-click on HKEY_LOCAL_MACHINE to expand it. Now click on Software under it. Similarly, navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList
Under ProfileList, locate to the SID key which something like “S-1-5-21-……bak”. The one .bak is the link to your inaccessible profile, delete .bak key then restart the computer to take effect.
It’s worked for me. Hope it helps for you.