diff --git a/src/common/plugins/plugin_manager.cpp b/src/common/plugins/plugin_manager.cpp
index 769e3e359..63797d441 100644
--- a/src/common/plugins/plugin_manager.cpp
+++ b/src/common/plugins/plugin_manager.cpp
@@ -182,10 +182,13 @@ void PluginManager::loadPlugins(QDir pluginsDirectory)
  */
 void PluginManager::loadPlugin(const QString& fileName)
 {
+	QFileInfo fin(fileName);
+	if (pluginFiles.find(fin.absoluteFilePath()) != pluginFiles.end())
+		throw MLException(fin.fileName() + " has been already loaded.");
+
 	checkPlugin(fileName);
 
 	//load the plugin depending on the type (can be more than one type!)
-	QFileInfo fin(fileName);
 	QPluginLoader loader(fin.absoluteFilePath());
 	QObject *plugin = loader.instance();
 	PluginFileInterface* ifp = dynamic_cast<PluginFileInterface *>(plugin);
@@ -214,6 +217,7 @@ void PluginManager::loadPlugin(const QString& fileName)
 	//of all plugins
 	ifp->plugFileInfo = fin;
 	allPlugins.push_back(ifp);
+	pluginFiles.insert(fin.absoluteFilePath());
 }
 
 void PluginManager::unloadPlugin(PluginFileInterface* ifp)
diff --git a/src/common/plugins/plugin_manager.h b/src/common/plugins/plugin_manager.h
index 1388f9648..517570074 100644
--- a/src/common/plugins/plugin_manager.h
+++ b/src/common/plugins/plugin_manager.h
@@ -98,8 +98,9 @@ public:
 	EditPluginFactoryRangeIterator editPluginFactoryIterator(bool iterateAlsoDisabledPlugins = false) const;
 
 private:
-	//all plugins (except Edit plugins)
+	//all plugins
 	std::vector<PluginFileInterface*> allPlugins;
+	std::set<QString> pluginFiles; //used to check if a plugin file has been already loaded
 
 	//IOMeshPlugins
 	std::vector<IOMeshPluginInterface*> ioMeshPlugins;