If you encounter “The User Profile Service service failed the sign-in. User profile cannot be loaded.” error on your Windows 10, it means your user profile has been corrupted. Furthermore, you cannot access Windows 10. But fortunately, this annoying error could be fixed easily. Go with this small guide, get rid of the error now.
Here you’ll learn the tried-and-true method for the error.
Note: Before we go, you can try to reboot your Windows 10, if the error still occur, follow the fix below.
Fix your corrupt user profile by correcting its registry value:
1) Follow this guide to boot your Windows 10 into safe mode.
2) In safe mode, open the Run box by pressing Windows logo key + R key together.
Then type regedit in the box and hit Enter.
If prompted by User Account Control, click YES.
3) Now Registry Editor window pops up. Go to HKEY_LOCAL_MACHINE > SOFTWARE > Microsoft > Windows NT > CurrentVersion > ProfileList
4) Check ProfileImagePath in each folder with the name has S-1-5 in ProfileList.
Find out the one with your user account data.
Case 1: If you have two folders starting with S-1-5 relates to your account and one of them ended with .bak, you have to rename the .bak folder. To do this, follow these steps:
a) Right-click the folder without .bak.
Then click Rename to add .ba at the end.
b) Right-click the folder that is named .bak.
Then click Rename to remove .bak.
c) Right-click the folder that is named .ba.
Then click Rename to change the .ba to .bak.
Case 2: If you have only one folder starting with S-1-5 relates to your account and ends with .bak. Right-click the folder, and then click Rename to remove .bak.
5) Double-click on RefCount in the folder your account relates to and end without .bak.
Then change its value into 0 and click OK.
Note: If you don’t see a RefCount file, please create a new DWORD named RefCount first and set its value to 0.
6) Double-click on State in the same folder.
Then change its value into 0, too.
Note: If you don’t see a State file, please create a new DWORD named State first and set its value to 0.
7) Close the Registry Editor window and restart your computer to log in with your account to check if the error still occur.