diff --git a/tryton/bus.py b/tryton/bus.py
index 8920e825e6..b27c80e6cf 100644
--- a/tryton/bus.py
+++ b/tryton/bus.py
@@ -72,7 +72,7 @@ def _listen(connection):
                     logger.info("Bus not supported")
                     break
             logger.error(
-                "An exception occured while connecting to the bus."
+                "An exception occurred while connecting to the bus. "
                 "Sleeping for %s seconds",
                 wait, exc_info=error)
             time.sleep(min(wait, bus_timeout))
diff --git a/tryton/common/completion.py b/tryton/common/completion.py
index 1860166d4e..5bd4157c4d 100644
--- a/tryton/common/completion.py
+++ b/tryton/common/completion.py
@@ -67,7 +67,7 @@ def update_completion(entry, record, field, model, domain=None):
                 process_exception=False, callback=callback)
         except Exception:
             logger.warning(
-                _("Unable to search for completion of %s") % model,
+                "Unable to search for completion of %s", model,
                 exc_info=True)
         return False
     search_text = entry.get_text()
diff --git a/tryton/gui/window/email_.py b/tryton/gui/window/email_.py
index 9b9a38a607..79dbb8669d 100644
--- a/tryton/gui/window/email_.py
+++ b/tryton/gui/window/email_.py
@@ -59,7 +59,7 @@ class EmailEntry(Gtk.Entry):
                 results = results()
             except (TrytonError, TrytonServerError):
                 logger.warning(
-                    _("Unable to complete email entry"), exc_info=True)
+                    "Unable to complete email entry", exc_info=True)
                 results = []
             if text != self.get_text():
                 return False
diff --git a/tryton/gui/window/view_form/screen/screen.py b/tryton/gui/window/view_form/screen/screen.py
index 96619d604c..cd52725245 100644
--- a/tryton/gui/window/view_form/screen/screen.py
+++ b/tryton/gui/window/view_form/screen/screen.py
@@ -837,8 +837,8 @@ class Screen(SignalEvent):
                 selected_nodes = json.loads(selected_nodes)
             except RPCException:
                 logger.warn(
-                    _('Unable to get view tree state for %s')
-                    % self.model_name)
+                    'Unable to get view tree state for %s',
+                    self.model_name)
             self.tree_states[parent][view.children_field] = (
                 expanded_nodes, selected_nodes)
         if view.view_type == 'tree':
diff --git a/tryton/gui/window/wizard.py b/tryton/gui/window/wizard.py
index 02d2237342..a41937fe0a 100644
--- a/tryton/gui/window/wizard.py
+++ b/tryton/gui/window/wizard.py
@@ -155,8 +155,8 @@ class Wizard(InfoBar):
                 process_exception=False, callback=end_callback)
         except Exception:
             logger.warn(
-                _("Unable to delete wizard %s") % self.session_id,
-                exc_info=True)
+                "Unable to delete session %s of wizard %s",
+                self.session_id, self.action, exc_info=True)
 
     def clean(self):
         for widget in self.widget.get_children():