diff --git a/src/slic3r/GUI/CalibrationWizard.cpp b/src/slic3r/GUI/CalibrationWizard.cpp
index ebb55ee158..91baab36ce 100644
--- a/src/slic3r/GUI/CalibrationWizard.cpp
+++ b/src/slic3r/GUI/CalibrationWizard.cpp
@@ -169,14 +169,14 @@ void CalibrationWizard::set_cali_method(CalibrationMethod method)
 bool CalibrationWizard::save_preset(const std::string &old_preset_name, const std::string &new_preset_name, const std::map<std::string, ConfigOption *> &key_values, std::string& message)
 {
     if (new_preset_name.empty()) {
-        message = L("The name cannot be empty.");
+        message = _u8L("The name cannot be empty.");
         return false;
     }
 
     PresetCollection *filament_presets = &wxGetApp().preset_bundle->filaments;
     Preset* preset = filament_presets->find_preset(old_preset_name);
     if (!preset) {
-        message = (boost::format(L("The selected preset: %1% is not found.")) % old_preset_name).str();
+        message = (boost::format(_u8L("The selected preset: %1% is not found.")) % old_preset_name).str();
         return false;
     }
 
@@ -188,12 +188,12 @@ bool CalibrationWizard::save_preset(const std::string &old_preset_name, const st
     Preset *new_preset = filament_presets->find_preset(new_name);
     if (new_preset) {
         if (new_preset->is_system) {
-            message = L("The name cannot be the same as the system preset name.");
+            message = _u8L("The name cannot be the same as the system preset name.");
             return false;
         }
 
         if (new_preset != preset) {
-            message = L("The name is the same as another existing preset name");
+            message = _u8L("The name is the same as another existing preset name");
             return false;
         }
         if (new_preset != &filament_presets->get_edited_preset()) new_preset = &temp_preset;
@@ -214,7 +214,7 @@ bool CalibrationWizard::save_preset(const std::string &old_preset_name, const st
     // Preset* preset = &m_presets.preset(it - m_presets.begin(), true);
     if (!new_preset) {
         BOOST_LOG_TRIVIAL(info) << "create new preset failed";
-        message = L("create new preset failed.");
+        message = _u8L("create new preset failed.");
         return false;
     }
 
@@ -1079,7 +1079,7 @@ void FlowRateWizard::on_cali_save()
 
             std::string message;
             if (!save_preset(old_preset_name, into_u8(new_preset_name), key_value_map, message)) {
-                MessageDialog error_msg_dlg(nullptr, message, wxEmptyString, wxICON_WARNING | wxOK);
+                MessageDialog error_msg_dlg(nullptr, from_u8(message), wxEmptyString, wxICON_WARNING | wxOK);
                 error_msg_dlg.ShowModal();
                 return;
             }
@@ -1358,7 +1358,7 @@ void MaxVolumetricSpeedWizard::on_cali_save()
 
     std::string message;
     if (!save_preset(old_preset_name, new_preset_name, key_value_map, message)) {
-        MessageDialog error_msg_dlg(nullptr, message, wxEmptyString, wxICON_WARNING | wxOK);
+        MessageDialog error_msg_dlg(nullptr, from_u8(message), wxEmptyString, wxICON_WARNING | wxOK);
         error_msg_dlg.ShowModal();
         return;
     }