Hi,

In the Odoo 19.0-20250928 (Community Edition), in the Project Tasks, there are several views. All of them work (kanban, list, pivot, activities,..) except the Calendar view. When trying to switch the view, the error message appears "Oops, Something went wrong..." with a detailed error description as follows"

EDIT: I've posted to the wrong forum page. Please delete this post, I can't for some reason.

Odoo Server Error

RPC_ERROR
Odoo Server Error

Occured on odoo.mywebsite.com on model project.task on 2025-11-12 17:12:03 GMT

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/odoo/orm/domains.py", line 914, in __get_field
    field = model._fields[field_name]
            ~~~~~~~~~~~~~^^^^^^^^^^^^
KeyError: 'planned_date_begin'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/odoo/http.py", line 2279, in _serve_db
    return service_model.retrying(serve_func, env=self.env)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/odoo/service/model.py", line 184, in retrying
    result = func()
             ^^^^^^
  File "/usr/lib/python3/dist-packages/odoo/http.py", line 2326, in _serve_ir_http
    response = self.dispatcher.dispatch(rule.endpoint, args)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/odoo/http.py", line 2541, in dispatch
    result = self.request.registry['ir.http']._dispatch(endpoint)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/odoo/addons/base/models/ir_http.py", line 357, in _dispatch
    result = endpoint(**request.params)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/odoo/http.py", line 788, in route_wrapper
    result = endpoint(self, *args, **params_ok)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/odoo/addons/web/controllers/dataset.py", line 32, in call_kw
    return call_kw(request.env[model], method, args, kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/odoo/service/model.py", line 93, in call_kw
    result = method(recs, *args, **kwargs)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/odoo/addons/web/models/models.py", line 63, in web_search_read
    records = self.search_fetch(domain, specification.keys(), offset=offset, limit=limit, order=order)
              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/odoo/orm/models.py", line 1408, in search_fetch
    query = self._search(domain, offset=offset, limit=limit, order=order or self._order)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/odoo/orm/models.py", line 5361, in _search
    domain = domain.optimize_full(self)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/odoo/orm/domains.py", line 445, in optimize_full
    return self._optimize(model, OptimizationLevel.FULL)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/odoo/orm/domains.py", line 459, in _optimize
    previous, domain = domain, domain._optimize_step(model, next_level)
                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/odoo/orm/domains.py", line 653, in _optimize_step
    children = self._flatten(child._optimize(model, level) for child in self.children)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/odoo/orm/domains.py", line 608, in _flatten
    for child in children:
  File "/usr/lib/python3/dist-packages/odoo/orm/domains.py", line 653, in <genexpr>
    children = self._flatten(child._optimize(model, level) for child in self.children)
                             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/odoo/orm/domains.py", line 459, in _optimize
    previous, domain = domain, domain._optimize_step(model, next_level)
                               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/odoo/orm/domains.py", line 938, in _optimize_step
    field, property_name = self.__get_field(model)
                           ^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3/dist-packages/odoo/orm/domains.py", line 916, in __get_field
    self._raise("Invalid field %s.%s", model._name, field_name)
  File "/usr/lib/python3/dist-packages/odoo/orm/domains.py", line 901, in _raise
    raise error(message % (*args, self.field_expr, self.operator, self.value))
ValueError: Invalid field project.task.planned_date_begin in condition ('planned_date_begin', '=', False)

The above server error caused the following client error:
OwlError: An error occured in the owl lifecycle (see this Error's "cause" property)
    Error: An error occured in the owl lifecycle (see this Error's "cause" property)
        at handleError (https://odoo.mywebsite.com/web/assets/04c1e82/web.assets_web.min.js:762:101)
        at App.handleError (https://odoo.mywebsite.com/web/assets/04c1e82/web.assets_web.min.js:1420:29)
        at ComponentNode.initiateRender (https://odoo.mywebsite.com/web/assets/04c1e82/web.assets_web.min.js:854:19)

Caused by: RPC_ERROR: Odoo Server Error
    RPC_ERROR
        at makeErrorFromResponse (https://odoo.mywebsite.com/web/assets/04c1e82/web.assets_web.min.js:3180:163)
        at XMLHttpRequest.<anonymous> (https://odoo.mywebsite.com/web/assets/04c1e82/web.assets_web.min.js:3186:13)

The workaround is to select "All tasks" -> set Calendar -> choose only the desired project name on the right side, under the month view.