How to let standard user run an application without administrator previleges

I want to give my younger brother access to the games on my Windows 7 PC while using a standard user. But on startup, each program requests the admin password which my brother obviously shouldn't get (with an admin user I had 3 trojans and 9 malware programs on my computer within 2 weeks).

What are the reasons Windows asks for the admin password for a game? Why should the game need administrator rights?

I believe sometimes a program update may trigger a need for admin privileges. I want to say Steam has done this to me in the past, but I'm not certain.

If your brother isn't terribly clever, you could always replace the game shortcuts with batch scripts that use runas to start the game. Downside is that your password would be in plain text, and if he opens up the batch script he will be able to log in to your account anyway.

RunasSpc might do the trick for you if he does have some wits about him. You'll create and encrypted file to open the program under your (or any) admin user. Something like this:

Then create a shortcut to launch the game from his Desktop as with a path as follows:

c:\path_to_runasspc\runasspc.exe /cryptfile:"C:\Users\brother\somegame.spc"

Now he can launch only the games that you choose under your profile, from his profile.

There's an option at Lifehacker. Quick synopsis here, but read the link for full details:

1. Use Task Scheduler to create a task.
   1. Enable "Run with highest privileges"
   2. Enable "Allow task to be run on demand" or the equivalent option.
2. Create a shortcut on the desktop that points to:

   C:\Windows\System32\schtasks.exe /run /tn "FolderName\ScheduledTaskName"

   1. Don't forget to change the icon to the regular application's icon!

If a program is asking for administrative privelages (either through an embedded or external assembly manifest), you can override the elevation request, and force the application to run as a standard user.

For example, the program Game Cam insists that it be run as an administrator. It contains an embedded assembly manifest that contains the

runas="requireAdministrator"

entry. You can override this requirement; returning it to the default "as invoker". The way to do that is to add a compability entry to the Windows registry:

HKCU\Softare\Microsoft\Windows NT\CurrentVersion\AppCompatFlags
   D:\Programs\Game Cam V2\GameCamV2.exe = RUNASINVOKER

This overrides the request by the application to run as an administrator, and instead forces the application to run as a standard user.

The application might not handle running as a standard user. Most software developers are lazy, and don't bother to test their applications. So the application might crash and burn horribly.

But at least it is running as a standard user.