Possibly not the most secure solution but in my case I got a VM and want to autologin to a user on bootup of the Windows 10 TP (Technical Preview).
Here is how to do that.
1) Click on “Start” and in the search box type in “netplwiz“
should appear, which you click.
2) In the User Accounts Dialog Box untick “Users must enter a username and password to use this computer. On clicking OK you will be asked to provide the username and password for the account to be auto logged in on reboot.