diff --git a/src/slic3r/GUI/SyncAmsInfoDialog.cpp b/src/slic3r/GUI/SyncAmsInfoDialog.cpp
index b88c0d7605..a819464a86 100644
--- a/src/slic3r/GUI/SyncAmsInfoDialog.cpp
+++ b/src/slic3r/GUI/SyncAmsInfoDialog.cpp
@@ -1079,7 +1079,7 @@ void SyncAmsInfoDialog::check_empty_project()
         if (!temp_plate->get_objects_on_this_plate().empty()) {
             if (m_is_empty_project) { m_is_empty_project = false; }
             if (i < 9) {
-                m_plate_number_choices_str.Add("0" + std::to_wstring(i + 1));
+                m_plate_number_choices_str.Add(wxString("0") + std::to_wstring(i + 1));
             }
             else if (i == 9) {
                 m_plate_number_choices_str.Add("10");