Windows Autologon

* Windows registry:

1. Launch Regedit 
2. Navigate to:
   HKLM\Software\Microsoft\Windows NT\CurrentVersion\winlogon
   Set: AutoAdminLogon = 1 (one means on, zero means off.)
3. DefaultUserName. The value should reflect the user who you wish to logon automatically.  If this value does not exist, then right-click in the right pane, New, REG_SZ, name it, DefaultUserName.  Set the string value to the required UserName
4. DefaultPassword. The password of the previous user (If this value does not exist, then right-click in the right pane, New, REG_SZ, name it, DefaultUserPassword).
5. Finally, if it's a domain user, create a String Value called DefaultDomainName.  
   Set: DefaultDomainName = "OnlyYouKnowDomain"

* External application:

https://docs.microsoft.com/es-es/sysinternals/downloads/autologon

This application do the same as "windows registry mode" but in a pretty view.

1. Enter user name.
2. Write user's password.
3. Enter the domain
4. Click on "Enable"
5. Reboot the machine and check autologon.