diff --git a/cpdctrl_gui/ui/main_window.py b/cpdctrl_gui/ui/main_window.py
index 79c5033..30835c4 100644
--- a/cpdctrl_gui/ui/main_window.py
+++ b/cpdctrl_gui/ui/main_window.py
@@ -19,6 +19,7 @@ from .widgets.about import MarkdownView
 from .widgets.led_script import LedScriptViewer
 # from .widgets.treeview import TreeView
 
+import pickle
 import logging
 log = logging.getLogger(__name__)
 
@@ -101,9 +102,7 @@ class MainWindow(QMainWindow):
             def dropEvent(self, event):
                 for url in event.mimeData().urls():
                     file_path = url.path()[1:]
-                    if file_path.endswith("csv"):
-                        self.call_f(file_path)
-                        return
+                    self.call_f(file_path)
         # Right: Tabs: Script, Plot
         self.w_right_tab = RightTab(self.measurement_load)
         layout.addWidget(self.w_right_tab)
@@ -381,7 +380,6 @@ class MainWindow(QMainWindow):
             elif file_path.endswith(".pkl"):
                 AppConfig.MAIN_CFG.set("tmp_last_measurement_save_ext", "pkl")
                 data = self.data_collector.get_data()
-                import pickle
                 with open(file_path, "wb") as f:
                     pickle.dump(data, f)
             else:
@@ -391,11 +389,18 @@ class MainWindow(QMainWindow):
             self.set_status(f"Aborted saving data, no file selected")
 
     def measurement_load(self, filepath):
+        log.info(f"Loading measurement data from '{filepath}'")
         if self.measurement_is_running():
             QMessageBox.critical(self, "Measurement running", "Can not load data while measurement is running")
             return
         if os.path.isfile(filepath):
-            data, mdata = DataCollector.load_data_from_csv(filepath)
+            if filepath.endswith(".pkl"):
+                with open(filepath, "rb") as file:
+                    data, mdata = pickle.load(file)
+            elif filepath.endswith(".csv"):
+                data, mdata = DataCollector.load_data_from_csv(filepath)
+            else:
+                raise NotImplementedError(f"Unknown file extension in path: '{filepath}'.\nOnly .pkl and .csv can be loaded")
         elif os.path.isdir(filepath):
             data, mdata = DataCollector.load_data_from_dir(filepath)
         else: