Simulating Users with the RunAs Command

One of the problems with writing applications, administering any network, or understanding system issues is to ensure that you see things from the user’s perspective. It doesn’t matter what your forte might be (programmer, administrator, DBA, manager, or the like), getting the user view of things is essential or your efforts are doomed to failure. Of course, this means seeing what the user sees. Anyone can run an application at the administrator level with good success, but the user level is another story because the user might not have access to resources or rights to perform tasks correctly.

Most knowledgeable users know that you can simulate an administrator by right clicking the application and choosing Run As Administrator from the context menu. In fact, if you Shift+Right Click the application, you’ll see an entry for Run As A Different User on the context menu that allows you to start the application as any user on the system. However, the GUI has limitations, including an inability to use this approach for batch testing of an application. In addition, this approach uses the RunAs command defaults, such as loading the user’s profile, which could cause the application to react differently than it does on the user’s system because it can’t find the resources it needs on your system.

A more practical approach is to use the RunAs command directly to get the job done. You can see some basic coverage of this command on page 480 of Windows Command-Line Administration Instant Reference. To gain a basic appreciation of how the user views things, simply type RunAs /User:UserName Command and press Enter (where UserName is the user’s fully qualified logon name including domain and Command is the command you wish to test). For example, if you want to see how Notepad works for user John, you’d type RunAs /User:John Notepad and press Enter. At this point, the RunAs command will ask for the user’s password. You’ll need to ask the user to enter it for you, but at that point, you can work with the application precisely as the user works with it.

Of course, many commands require that you provide command line arguments. In order to use command line arguments, you must enclose the entire command in double quotes. For example, if you want to open a file named Output.TXT located in the C:\MyDocs folder using Notepad and see it in precisely the same way that the user sees it, you’d type RunAs /User:John “Notepad C:\MyDocs\Output.TXT” and press Enter.

In some cases, you need to test the application using the users credentials, but find that the user’s profile gets in the way. The user’s system probably isn’t set up the same as your system, so you need your profile so that the system can find things on your machine and not on the user’s machine. In this case, you add the /NoProfile command line switch to use your profile. It’s a good idea to try the command with the user’s profile first, just to get things as close as you can to what the user sees. The default is to load the user’s profile, so you don’t have to do anything special to obtain this effect.

An entire group of users might experience a problem with an application. In this case, you don’t necessarily want to test with a particular user’s account, but with a specific trust level. You can see the trust levels setup on your system by typing RunAs /ShowTrustLevels and pressing Enter. To run an application using a trust level, use the /TrustLevel command line switch. For example, to open Output.TXT as a basic user, you’d type RunAs /TrustLevel:0x20000 “Notepad C:\MyDocs\Output.TXT” and press Enter. The basic trust levels are:

 

  • 0x40000 – System
  • 0x30000 – Administrator
  • 0x20000 – Basic User
  • 0x10000 – Untrusted User

Many people are experiencing problems using the /ShowTrustLevels and /TrustLevel command line switches with newer versions of Windows such as Vista and Windows 7. The consensus seems to be that Microsoft has changed things with the introduction of UAC and that you’ll need to work with the new Elevation Power Toys to get the job done. I’d be interested in hearing about people’s experiences. Contact me at John@JohnMuellerBooks.com.