diff --git a/src/mainwindow.cpp b/src/mainwindow.cpp
--- a/src/mainwindow.cpp
+++ b/src/mainwindow.cpp
@@ -252,7 +252,7 @@
     connect(viewer3D, &Viewer3D::droppedUrls, this, &MainWindow::processDropEvent);
 
     connect(m_gcodeEditor, &GCodeEditorWidget::currentFileChanged, this, [viewer3D](const QUrl & url) {
-        viewer3D->drawModel(url.toString());
+        viewer3D->drawModel(url.toLocalFile());
     });
 
     setupButton("welcome", i18n("&Welcome"), QIcon::fromTheme("go-home", QIcon(QString(":/%1/home").arg(m_theme))), new WelcomeWidget(this));
@@ -319,7 +319,7 @@
     if (!fileName.isEmpty()) {
 
         m_lateral.get<GCodeEditorWidget>("gcode")->loadFile(fileName);
-        m_lateral.get<Viewer3D>("3d")->drawModel(fileName.toString());
+        m_lateral.get<Viewer3D>("3d")->drawModel(fileName.toLocalFile());
         // Make 3dview focused when opening a file
         if (m_openFiles.isEmpty() && m_lateral.m_stack->currentWidget() == m_lateral.get<WelcomeWidget>("welcome")) {
             m_lateral.getButton<QPushButton>("3d")->setChecked(true);
diff --git a/src/widgets/atcoreinstancewidget.cpp b/src/widgets/atcoreinstancewidget.cpp
--- a/src/widgets/atcoreinstancewidget.cpp
+++ b/src/widgets/atcoreinstancewidget.cpp
@@ -324,11 +324,11 @@
             , i18n("No filename sent from calling method, please check and try again.")
         );
         return;
-    } else if (!QFileInfo(fileName.toString()).isReadable()) {
+    } else if (!QFileInfo(fileName.toLocalFile()).isReadable()) {
         QMessageBox::critical(
             this
             , i18n("File not found")
-            , i18n("%1 \nIs not readable, please check and try again.", fileName.toString())
+            , i18n("%1 \nIs not readable, please check and try again.", fileName.toLocalFile())
         );
         return;
     }