diff --git a/src/calibre/gui2/actions.py b/src/calibre/gui2/actions.py
index 5a3a5a7059..eae4dc76f8 100644
--- a/src/calibre/gui2/actions.py
+++ b/src/calibre/gui2/actions.py
@@ -927,6 +927,14 @@ class SaveToDiskAction(object): # {{{
                 _('Choose destination directory'))
         if not path:
             return
+        dpath = os.path.abspath(path).replace('/', os.sep)
+        lpath = self.library_view.model().db.library_path.replace('/', os.sep)
+        if dpath.startswith(lpath):
+            return error_dialog(self, _('Not allowed'),
+                    _('You are tying to save files into the calibre '
+                      'library. This can cause corruption of your '
+                      'library. Save to disk is meant to export '
+                      'files from your calibre library elsewhere.'), show=True)
 
         if self.current_view() is self.library_view:
             from calibre.gui2.add import Saver