9 answers
Instead of a formula, create a new Date or Datetime field, and update it to NOW() via a Workflow Field Update or via a trigger, whenever you detect that the Checkbox value has been changed from False to True.
Instead of a formula, create a new Date or Datetime field, and update it to NOW() via a Workflow Field Update or via a trigger, whenever you detect that the Checkbox value has been changed from False to True.
