Start a program in an active user session from a service?

Question

How can I start a program in an active user session from a running .NET background process. Basically I have a .NET application running as a service and I want that application to launch a specific windowed application on the users desktop when certain events happen.

How can I do this?

This question is related to this one: http://stackoverflow.com/questions/1727828/start-a-program-in-active-user-session-with-powershell-remoting

Update
Using Process.Start alone will not work here since it launches the application in the current application session. It doesn't launch the application in a specific users active desktop session.

Answer 1

The CreateProcessWithLogonW function will allow you to pass in the credentials of the user you want the application to run as.

Also, note that if you go down this route you do need to pass in the STARTUPINFO structure so that it starts on the right desktop, and not just leave it null.

Answer 2

Is it feasible for you to build some kind of lightweight listener application that the user would run in the background? Presumably your service could communicate with the listener and have the listener instantiate the windowed app since it's running in the user's context.

Answer 3

Look into the Log On context of the windows service as shown here. This allows interaction of the windows service with a desktop session.