diff --git a/jupyter_server/extension/application.py b/jupyter_server/extension/application.py index 932263e702..108b270670 100644 --- a/jupyter_server/extension/application.py +++ b/jupyter_server/extension/application.py @@ -213,11 +213,15 @@ def _default_url(self): def _default_serverapp(self): # load the current global instance, if any if ServerApp.initialized(): - return ServerApp.instance() - else: - # serverapp accessed before it was defined, - # declare an empty one - return ServerApp() + try: + return ServerApp.instance() + except Exception: + # error retrieving instance, e.g. MultipleInstanceError + pass + + # serverapp accessed before it was defined, + # declare an empty one + return ServerApp() _log_formatter_cls = LogFormatter