Traceback (most recent call last):
  File "/opt/odoo/odoo-server/openerp/http.py", line 543, in _handle_exception
    return super(JsonRequest, self)._handle_exception(exception)
  File "/opt/odoo/odoo-server/openerp/http.py", line 580, in dispatch
    result = self._call_function(**self.params)
  File "/opt/odoo/odoo-server/openerp/http.py", line 316, in _call_function
    return checked_call(self.db, *args, **kwargs)
  File "/opt/odoo/odoo-server/openerp/service/model.py", line 118, in wrapper
    return f(dbname, *args, **kwargs)
  File "/opt/odoo/odoo-server/openerp/http.py", line 313, in checked_call
    return self.endpoint(*a, **kw)
  File "/opt/odoo/odoo-server/openerp/http.py", line 809, in __call__
    return self.method(*args, **kw)
  File "/opt/odoo/odoo-server/openerp/http.py", line 409, in response_wrap
    response = f(*args, **kw)
  File "/opt/odoo/odoo-server/addons/web/controllers/main.py", line 944, in call_kw
    return self._call_kw(model, method, args, kwargs)
  File "/opt/odoo/odoo-server/addons/web/controllers/main.py", line 936, in _call_kw
    return getattr(request.registry.get(model), method)(request.cr, request.uid, *args, **kwargs)
  File "/opt/odoo/odoo-server/openerp/api.py", line 268, in wrapper
    return old_api(self, *args, **kwargs)
  File "/opt/odoo/odoo-server/addons/point_of_sale/point_of_sale.py", line 672, in create_from_ui
    order_id = self._process_order(cr, uid, order, context=context)
  File "/opt/odoo/odoo-server/openerp/api.py", line 268, in wrapper
    return old_api(self, *args, **kwargs)
  File "/opt/odoo/odoo-server/addons/point_of_sale/point_of_sale.py", line 618, in _process_order
    if session.state == 'closing_control' or session.state == 'closed':
  File "/opt/odoo/odoo-server/openerp/fields.py", line 841, in __get__
    return record._cache[self]
  File "/opt/odoo/odoo-server/openerp/models.py", line 6053, in __getitem__
    return value.get() if isinstance(value, SpecialValue) else value
  File "/opt/odoo/odoo-server/openerp/fields.py", line 56, in get
    raise self.exception
MissingError: ('MissingError', u'Uno de los documentos al que est\xe1 intentado acceder ha sido eliminado. Int\xe9ntelo por favor de nuevo tras actualizar.')