diff --git a/invesalius/control.py b/invesalius/control.py
index ebcf206..674c08d 100755
--- a/invesalius/control.py
+++ b/invesalius/control.py
@@ -261,7 +261,7 @@ class Controller():
         if (data):
             if not(self.progress_dialog):
                 self.progress_dialog = dialog.ProgressDialog(
-                                    maximum = data[1])
+                                    maximum = data[1], abort=1)
             else:
                 if not(self.progress_dialog.Update(data[0],message)):
                     self.progress_dialog.Close()
diff --git a/invesalius/gui/dialogs.py b/invesalius/gui/dialogs.py
index a61a77e..0aa949d 100644
--- a/invesalius/gui/dialogs.py
+++ b/invesalius/gui/dialogs.py
@@ -90,19 +90,20 @@ def ShowNumberDialog(message, value=0):
 
 
 class ProgressDialog(object):
-    def __init__(self, maximum):
+    def __init__(self, maximum, abort=False):
         self.title = "InVesalius 3"
         self.msg = _("Loading DICOM files")
         self.maximum = maximum
         self.current = 0
-        self.style = wx.PD_CAN_ABORT | wx.PD_APP_MODAL
+        self.style = wx.PD_APP_MODAL
+        if abort:
+            self.style = wx.PD_APP_MODAL | wx.PD_CAN_ABORT
+            
         self.dlg = wx.ProgressDialog(self.title,
                                      self.msg,
                                      maximum = self.maximum,
                                      parent = None,
-                                     style = wx.PD_CAN_ABORT
-                                      | wx.PD_APP_MODAL,
-                                     )
+                                     style  = self.style)
 
         self.dlg.Bind(wx.EVT_BUTTON, self.Cancel)
         self.dlg.SetSize(wx.Size(250,150))
diff --git a/invesalius/gui/frame.py b/invesalius/gui/frame.py
index 4368799..ec8d0a7 100755
--- a/invesalius/gui/frame.py
+++ b/invesalius/gui/frame.py
@@ -93,7 +93,11 @@ class Frame(wx.Frame):
         ps.Publisher().subscribe(self.HideContentPanel, 'Hide content panel')
 
     def EndBusyCursor(self, pubsub_evt=None):
-        wx.EndBusyCursor()
+        try:        
+            wx.EndBusyCursor()
+        except wx._core.PyAssertionError:
+            #xEndBusyCursor(): no matching wxBeginBusyCursor() for wxEndBusyCursor()
+            pass
 
     def BeginBusyCursor(self, pubsub_evt=None):
         wx.BeginBusyCursor()
--
libgit2 0.21.2