diff --git a/main.cpp b/main.cpp
index c0a870d..d118f57 100644
--- a/main.cpp
+++ b/main.cpp
@@ -3,6 +3,18 @@
 #include <QApplication>
 #include <QTranslator>
 #include <QLocale>
+#include <QProcess>
+
+bool isAnotherInstanceRunning(const QString& processName)
+{
+    QProcess process;
+    process.start("tasklist", QStringList() << "/FI" << QString("IMAGENAME eq %1").arg(processName));
+    process.waitForFinished();
+    QString output = process.readAllStandardOutput();
+    int count = output.count(processName, Qt::CaseInsensitive);
+
+    return count > 1;
+}
 
 int main(int argc, char *argv[])
 {
@@ -10,6 +22,12 @@ int main(int argc, char *argv[])
     a.setStyle("fusion");
     a.setQuitOnLastWindowClosed(false);
 
+    const QString processName = "QuickSoundSwitcher.exe";
+    if (isAnotherInstanceRunning(processName)) {
+        qDebug() << "Another instance is already running. Exiting...";
+        return 0;
+    }
+
     QString mode = Utils::getTheme();
     QString color;
     QPalette palette = QApplication::palette();