How can I check for a running process per user session?

Question

I have a .NET application that I only allow to run a single process at a time of, however that app is used on Citrix boxes from time to time, and as such, can be run by mult

Answer 1

If Form1 launches non-background threads, and that Form1 exits, you've got a problem: the mutex is released but the process is still there. Something along the lines below is better IMHO:

static class Program {
    private static Mutex mutex;



    /// 

    /// The main entry point for the application.
    /// 
    [STAThread]
    static void Main() {
        bool createdNew = true;
        mutex = new Mutex(true, @"Global\Test", out createdNew);
        if (createdNew) {
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            Application.Run(new Form1());        
        }
        else {
            MessageBox.Show(
                "Application is already running",
                "Error",
                MessageBoxButtons.OK,
                MessageBoxIcon.Error
            );
        }
    }
}

The mutex won't be released as long as the primary application domain is still up. And that will be around as long as the application is running.