diff --git a/src/slic3r/GUI/Plater.cpp b/src/slic3r/GUI/Plater.cpp
index 842055298..074832d5a 100644
--- a/src/slic3r/GUI/Plater.cpp
+++ b/src/slic3r/GUI/Plater.cpp
@@ -3080,10 +3080,13 @@ unsigned int Plater::priv::update_background_process(bool force_validation, bool
 
 	//actualizate warnings
 	if (invalidated != Print::APPLY_STATUS_UNCHANGED) {
+        if (background_process.empty())
+            process_validation_warning(std::string());
 		actualize_slicing_warnings(*this->background_process.current_print());
         actualize_object_warnings(*this->background_process.current_print());
 		show_warning_dialog = false;
 		process_completed_with_error = false;
+        
 	}
 
     if (invalidated != Print::APPLY_STATUS_UNCHANGED && was_running && ! this->background_process.running() &&