Use Sysinternals Autologon. It stores the credentials in the registry more securely than other methods.
Autologon for Windows v3.10
https://technet.microsoft.com/en-us/sysinternals/autologon
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While it really is an extremely bad idea it is still possible. However, the user must have a password AND the password is revealed to anyone that has access to HKLM. Most likely your desired user is even in the Domain Admins group.
As described in TechNet documentation AutoAdminLogon, you can add
[HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindows NTCurrentVersionWinlogon]
"AutoAdminLogon"="1"
"DefaultUserName"="your-admin-account"
"DefaultDomainName"="yourdomain.local"
"DefaultPassword"="YourAdminPasswordRevealedToThePublicByAStupidAdmin"
If this is a test environment not connected to your network and you are using a local admin account please be welcome to do so. Otherwise: just don't do it.
ADDITION: This doesn't answer the original question, but I just wanted to add a notice that this is still a suitable way to create a non-authenticated "kiosk machine", if you also add
[HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindows NTCurrentVersionWinlogon]
"ForceAutoLogon"="1"
for logging the user automatically in right after logout. It your user is on Domain Guests group the profile will be automatically deleted on every logoff and a fresh profile created based on default profile. You could also change the shell for example if you want to launch a web browser instead of the default explorer.exe. Then, closing browser window will cause deletion of all cache and browsing history.
[HKEY_LOCAL_MACHINESOFTWAREMicrosoftWindows NTCurrentVersionWinlogon]
"Shell"="C:Program Files (x86)GoogleChromeApplicationchrome.exe"