Microsoft, for some fine reason, removed the built-in guest account in Windows 10. But it is still possible to add one manually, via a simple workaround that involves the good old Command Prompt.
Goes without saying that you must be signed on as an administrator to add a guest account.
But doing so will create a local account for users that do not have a permanent account on your PC. These guests or visitors will be able to use your PC without getting access to your personal files, and will not be able to install apps, open Windows Store applications, set up hardware, and change settings.
This is how you can add a guest account in Windows 10 via an elevated command prompt.
1. Type Command Prompt in Start.
2. Right click the icon and select Run as administrator.
3. If you get the UAC window asking you for permission to allow the app to make changes to your computer, click on Yes.
4. Simply type net user Name /add in the window to create a new account, substituting Name as whatever you want to call this guest account. You cannot call this new account Guest, but any other name will do.
Now, you will need to remove this new local account from the Users group, and add it to the Guests group in the operating system.
6. Type net localgroup Users Name /delete to remove it.
7. And net localgroup Guests Name /add to add it to Guests, and close the command prompt.
The account will be added to the login screen. If you want, you can add a password to this guest account. The profile folder for this guest account will be created the first time someone signs in, and you can manage this account like any other.