IndexError when reading Internal console history file

[Farah9494]

I have tried : conda install -f python.app and I still get the same following error message when I try to launch Spyder
Traceback (most recent call last):
File "/Users/farah/opt/anaconda3/lib/python3.9/site-packages/spyder/app/utils.py", line 281, in create_window
main.setup()
File "/Users/farah/opt/anaconda3/lib/python3.9/site-packages/spyder/app/mainwindow.py", line 875, in setup
PLUGIN_REGISTRY.register_plugin(self, PluginClass,
File "/Users/farah/opt/anaconda3/lib/python3.9/site-packages/spyder/api/plugin_registration/registry.py", line 274, in register_plugin
instance = self._instantiate_spyder5_plugin(
File "/Users/farah/opt/anaconda3/lib/python3.9/site-packages/spyder/api/plugin_registration/registry.py", line 152, in _instantiate_spyder5_plugin
plugin_instance = PluginClass(main_window, configuration=CONF)
File "/Users/farah/opt/anaconda3/lib/python3.9/site-packages/spyder/api/plugins/new_api.py", line 890, in init
super().init(parent, configuration=configuration)
File "/Users/farah/opt/anaconda3/lib/python3.9/site-packages/spyder/api/plugins/new_api.py", line 294, in init
self._container = container = self.CONTAINER_CLASS(
File "/Users/farah/opt/anaconda3/lib/python3.9/site-packages/spyder/plugins/console/widgets/main_widget.py", line 123, in init
self.shell = InternalShell( # TODO: Move to use SpyderWidgetMixin?
File "/Users/farah/opt/anaconda3/lib/python3.9/site-packages/spyder/plugins/console/widgets/internalshell.py", line 153, in init
super().init(parent, get_conf_path('history_internal.py'),
File "/Users/farah/opt/anaconda3/lib/python3.9/site-packages/spyder/plugins/console/widgets/shell.py", line 665, in init
ShellBaseWidget.init(self, parent, history_filename,
File "/Users/farah/opt/anaconda3/lib/python3.9/site-packages/spyder/plugins/console/widgets/shell.py", line 75, in init
self.history = self.load_history()
File "/Users/farah/opt/anaconda3/lib/python3.9/site-packages/spyder/plugins/console/widgets/shell.py", line 503, in load_history
if rawhistory[1] != self.INITHISTORY[1]:
IndexError: list index out of range

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/Users/farah/opt/anaconda3/bin/spyder", line 11, in
sys.exit(main())
File "/Users/farah/opt/anaconda3/lib/python3.9/site-packages/spyder/app/start.py", line 237, in main
mainwindow.main(options, args)
File "/Users/farah/opt/anaconda3/lib/python3.9/site-packages/spyder/app/mainwindow.py", line 1992, in main
mainwindow = create_window(MainWindow, app, splash, options, args)
File "/Users/farah/opt/anaconda3/lib/python3.9/site-packages/spyder/app/utils.py", line 283, in create_window
if main.console is not None:
File "/Users/farah/opt/anaconda3/lib/python3.9/site-packages/spyder/app/mainwindow.py", line 1088, in getattr
return self.get_plugin(self._INTERNAL_PLUGINS_MAPPING[attr])
File "/Users/farah/opt/anaconda3/lib/python3.9/site-packages/spyder/app/mainwindow.py", line 165, in get_plugin
raise SpyderAPIError(f'Plugin "{plugin_name}" not found!')
spyder.api.exceptions.SpyderAPIError: Plugin "internal_console" not found!

[ccordoba12]

Hey @Farah9494, thanks for reporting. Please open a terminal and run

spyder --reset

then start Spyder again. That should do the trick.

However, we'll fix this bug in our next version (5.4.0), to be released in a couple of weeks, so other users don't encounter it.