Windows 8 has an annoying feature - it automatically sign's in as the last user who shutdown the computer if his/her account is not protected with a password. That means if your mom opens the computer after you have shut it down, she will automatically get logged in to your account. Although she can log off and login to her account, its like a daily pain.

Preventing windows 8 auto login.

There is an easy way to prevent this and make Windows 8 ask for a user account to login each time. But first let's see some technicals.

Whether to directly login or not is decided based on a registry entry-
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Authentication\LogonUI\UserSwitch

If it is set to 1, Windows 8 will show a tile of users to select and if set to 0, it will resort to auto-login. But there is another problem. LoginUI.exe program which runs while starting up automatically sets this to 0. That means even if you manually set it to 1, it will only be in effect for the immediate next login. After that windows 8 will again resort to auto-login.

So the trick to prevent auto login in Windows 8 is to have this switch set to 0 every time somebody logs off. You can either do the trick yourself or use a tool mentioned at the end of this post.

Manually disabling auto-login.

1. Press Win+R keys to open the "Run" dialog box, type netplwiz and press enter.

2. In the window that comes up, check the option called "Users must enter a user name and password to use this computer".

3. Press Win+R again and this time type gpedit.msc. This will open the Local Group Policy Editor. On the left-pane, expand to
User Configuration -> Windows Settings -> scripts(Login/Logoff).
Now double click on Logoff on the right pane and then click on the Add button.

4. In the "Add a script" dialog that comes up, copy-paste the following

Script name -
C:\Windows\System32\reg.exe

Script Parameters-
HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Authentication\LogonUI\UserSwitch /v Enabled /t REG_DWORD /d 1 /f

Click "Ok" and you are done. What you just did is to create a script which sets the culprit registry entry to 1 every time somebody logs off. This makes sure any body who starts the computer will always see the login screen with a tile of users. Cool isn't it :)

If you are skeptical of doing it yourself, you can as well use this handy tool "User List Expander" which also does the same thing.

Also see: Get back the Windows 7 style Start button in Windows 8.