Error when trying to save general options in Odoo 14

When I try to save any config I'm getting the following error:

Error: Odoo Server Error

ValueError: Invalid field 'recaptcha_public_key' on model 'res.config.settings'

The complete trace is the following:

    Odoo Server Error
Traceback (most recent call last):
  File "C:\Program Files\Odoo 14.0.20210511\server\odoo\addons\base\models\ir_http.py", line 237, in _dispatch
    result = request.dispatch()
  File "C:\Program Files\Odoo 14.0.20210511\server\odoo\http.py", line 683, in dispatch
    result = self._call_function(**self.params)
  File "C:\Program Files\Odoo 14.0.20210511\server\odoo\http.py", line 359, in _call_function
    return checked_call(self.db, *args, **kwargs)
  File "C:\Program Files\Odoo 14.0.20210511\server\odoo\service\model.py", line 94, in wrapper
    return f(dbname, *args, **kwargs)
  File "C:\Program Files\Odoo 14.0.20210511\server\odoo\http.py", line 347, in checked_call
    result = self.endpoint(*a, **kw)
  File "C:\Program Files\Odoo 14.0.20210511\server\odoo\http.py", line 912, in __call__
    return self.method(*args, **kw)
  File "C:\Program Files\Odoo 14.0.20210511\server\odoo\http.py", line 531, in response_wrap
    response = f(*args, **kw)
  File "C:\Program Files\Odoo 14.0.20210511\server\odoo\addons\web\controllers\main.py", line 1389, in call_kw
    return self._call_kw(model, method, args, kwargs)
  File "C:\Program Files\Odoo 14.0.20210511\server\odoo\addons\web\controllers\main.py", line 1381, in _call_kw
    return call_kw(request.env[model], method, args, kwargs)
  File "C:\Program Files\Odoo 14.0.20210511\server\odoo\api.py", line 394, in call_kw
    result = _call_kw_model_create(method, model, args, kwargs)
  File "C:\Program Files\Odoo 14.0.20210511\server\odoo\api.py", line 374, in _call_kw_model_create
    result = method(recs, *args, **kwargs)
  File "<decorator-gen-96>", line 2, in create
  File "C:\Program Files\Odoo 14.0.20210511\server\odoo\api.py", line 323, in _model_create_single
    return create(self, arg)
  File "C:\Program Files\Odoo 14.0.20210511\server\odoo\addons\base\models\res_config.py", line 783, in create
    return super(ResConfigSettings, self).create(values)
  File "<decorator-gen-65>", line 2, in create
  File "C:\Program Files\Odoo 14.0.20210511\server\odoo\api.py", line 344, in _model_create_multi
    return create(self, [arg])
  File "C:\Program Files\Odoo 14.0.20210511\server\odoo\addons\base\models\ir_fields.py", line 533, in create
    recs = super().create(vals_list)
  File "<decorator-gen-13>", line 2, in create
  File "C:\Program Files\Odoo 14.0.20210511\server\odoo\api.py", line 345, in _model_create_multi
    return create(self, arg)
  File "C:\Program Files\Odoo 14.0.20210511\server\odoo\models.py", line 3825, in create
    raise ValueError("Invalid field %r on model %r" % (key, self._name))
Exception

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "C:\Program Files\Odoo 14.0.20210511\server\odoo\http.py", line 639, in _handle_exception
    return super(JsonRequest, self)._handle_exception(exception)
  File "C:\Program Files\Odoo 14.0.20210511\server\odoo\http.py", line 315, in _handle_exception
    raise exception.with_traceback(None) from new_cause
ValueError: Invalid field 'recaptcha_public_key' on model 'res.config.settings'

That's because some module is not installed. To find out the module name, search the odoo source code for recaptcha_public_key.

We can see the module name is google_recaptcha:

In your odoo intance system, open the Apps page, search that module and installing it should resolve your problem.

Or you can install it by command line, see below. You will need to restart the server after that:

./odoo-bin -d <yourdbname> -i google_recaptcha