Add messages

Author: maxcapodi78

src/ansys/aedt/core/application/design.py

@@ -1604,6 +1604,8 @@ def oproject(self, proj_name: str = None) -> None:
                             raise RuntimeError("Project is locked. Close or remove the lock before proceeding.")
                     self._oproject = self.odesktop.OpenProject(proj_name)
                     pname = self.check_if_project_is_loaded(proj_name)
+                    if not pname:
+                        raise Exception("Failed to open project due to unexpected reason. Check it and retry.")
                     self._oproject = self.desktop_class.active_project(pname)
                     if not is_windows and settings.aedt_version:
                         time.sleep(1)