Some Windows 10 Insiders on Build 20226 have reported not being able to log in to their user profile(s) as expected.
Microsoft has now provided a work-around for help with the issue. It is only intended for build 20226 and will not apply to users on a different build.
To bypass this issue, please complete the following steps:
Note: the included steps assume your Windows installation is defaulted to the C: drive. If you have installed Windows on a different drive letter, please replace c: with the proper drive letter for your installation.
If your account is an Administrator account on the affected device:
- When you see the “We can’t sign into your account” dialogue, click the Close button.
- Open an elevated Command Prompt window.
- Enter and submit the following commands one line at a time:
- cd c:\users\%username%
- takeown /F ntuser.dat*
- icacls ntuser.dat* /reset
- icacls ntuser.dat* /setowner “SYSTEM”
- Sign out.
- You will stop seeing the above dialog on your next sign-in.
If your account is NOT an Administrator account on the affected device:
- When you see the “We can’t sign into your account” dialogue, click the Close button.
- Open a standard Command Prompt window.
- Enter the following command:
- Echo %username%
- (Make note of the returned username, you will use it in step 6)
- Close the standard Command Prompt window.
- Open an elevated Command Prompt window.
- Enter and submit the following commands one line at a time:
- cd c:\users\username
- takeown /F ntuser.dat*
- icacls ntuser.dat* /reset
- icacls ntuser.dat* /setowner “SYSTEM”
- Sign out
- You will stop seeing the above dialog on your next sign-in
If these steps don’t resolve the issue for you on build 20226, you may also complete a rollback to your previous build to bypass. You may then reinstall build 20226 and you will not encounter the issue a second time.
The cause for the bug has been identified and a fix is being developed.