Program.cs

using System;
using System.Windows.Forms;
using System.Threading;

namespace SimpleSvmManager;

static class Program
{
    static Mutex mutex = new Mutex(true, "{SimpleSvmManager-Unique-Mutex-12345}");

    [STAThread]
    static void Main()
    {
        if (!mutex.WaitOne(TimeSpan.Zero, true))
        {
            MessageBox.Show("Program is already running in the background!\nPlease check the system tray icon at the bottom right.", "SimpleSvm", MessageBoxButtons.OK, MessageBoxIcon.Warning);
            return;
        }

        // Single-binary flow: no separate watchdog, cleanup is tied directly to this EXE.
        AppDomain.CurrentDomain.UnhandledException += (s, e) => Form1.EmergencyCleanup();
        Application.ThreadException += (s, e) => Form1.EmergencyCleanup();
        AppDomain.CurrentDomain.ProcessExit += (s, e) => Form1.EmergencyCleanup();

        Application.EnableVisualStyles();
        Application.SetCompatibleTextRenderingDefault(false);
        Application.Run(new Form1());
    }    
}