diff --git a/src/libslic3r/PresetBundle.cpp b/src/libslic3r/PresetBundle.cpp
index e9e519c84..175c1c3d4 100644
--- a/src/libslic3r/PresetBundle.cpp
+++ b/src/libslic3r/PresetBundle.cpp
@@ -1831,6 +1831,11 @@ void PresetBundle::set_calibrate_printer(std::string name)
 std::set<std::string> PresetBundle::get_printer_names_by_printer_type_and_nozzle(const std::string &printer_type, std::string nozzle_diameter_str)
 {
     std::set<std::string> printer_names;
+
+    /* unknown or empty printer type */
+    if (printer_type.empty())
+        return printer_names;
+
     if ("0.0" == nozzle_diameter_str || nozzle_diameter_str.empty()) {
         nozzle_diameter_str = "0.4";
     }
diff --git a/src/slic3r/GUI/GUI_App.cpp b/src/slic3r/GUI/GUI_App.cpp
index c0dc8dab9..4f3d9c0c2 100644
--- a/src/slic3r/GUI/GUI_App.cpp
+++ b/src/slic3r/GUI/GUI_App.cpp
@@ -4891,7 +4891,7 @@ void GUI_App::process_network_msg(std::string dev_id, std::string msg)
         else if (msg == "update_firmware_studio") {
             BOOST_LOG_TRIVIAL(info) << "process_network_msg, firmware internal error";
             if (!m_show_error_msgdlg) {
-                MessageDialog msg_dlg(nullptr, _L("Firmware internal error, please try to upgrade firmware version."), "", wxAPPLY | wxOK);
+                MessageDialog msg_dlg(nullptr, _L("Internal error. Please try upgrading the firmware and Studio version. If the issue persists, contact customer support."), "", wxAPPLY | wxOK);
                 m_show_error_msgdlg = true;
                 auto modal_result = msg_dlg.ShowModal();
                 m_show_error_msgdlg = false;