What Is User Principal Name (UPN)?

You might think of your UPN as your email address, but that's only part of the story. The whole story is: your User Principal Name (UPN) is your email address plus the domain name that comes after the @ sign. Let's break it down: Your username is used to log in to Windows Active Directory. It usually has a combination of letters and numbers unique to you—so no one else can have your username. It has to be at least six characters long. So then, what's this "domain name"? It's basically like an extension on top of your username—it identifies which company or organization you work for, so they can tell who you are when they send out messages or emails to employees or members. So if you know your name is John Smith, and you work for Example Company Inc., you'd have a UPN like this jsmith@examplecompanyinc.com. We've all seen user names like "daniel. smith", "Jane. doe", and "john. smith". Have you ever wondered what those user names are? We'll tell you: It's a User Principal Name user; Principal Names (UPNs) are names you can use to authenticate yourself on the Windows operating system. You can also use them to abbreviate some long domain name lists. The UPN is also used to obtain a user's account in the Active Directory, which can be queried using the Active Directory Service Interface. This library type provides an interface to different kinds of directories, such as the user account database used by Windows. To query the account of a user using the Active Directory Service Interface, you must first obtain the UPN of the user. You can do this with the GetUser function. Once you have the UPN, you can use the FindByIdentity function to query the user's account information.