in reply to Using Perl to write application to interact with users on Windows OS

You probably need to take a look at Dave Roth's Win32::AdminMisc.

In particular, 

CreateProcessAsUser($CommandString [, $DefaultDirectory] [, %Config]);

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To use that call, you would need to LogonAsUser(), which requires that you:

  1. Know who the current user is.
  2. Have the correct authentication to log on as them.

None of which is discoverable by user 'LocalSystem'--by design. (Local System is actually quite a limited account deliberately!).

An alternative, is to have the user install the service to run under their account. This can be specified when the service is installed, or modified (by the user) through the Control panel->Administrative tools->Services->Properties->Log On tab.

On that same tab, you will also see a check box that offers the possibility for the a service that is "Logged on as 'Local System Account'" to "Allow service to interact with Desktop".

When checked, the service process is created with a message thread which allows it to create GUI windows and dialogs to interact with the user--directly from the service process without the need to create a second process as some other user.

Of course, it still only has LocalSystem permissions.

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