Change the base type of {0} so that it no longer extends {1}. This base exception type does not provide any additional value ...

Change the base type of {0} so that it no longer extends {1}. This base exception type does not provide any additional value for framework classes. Extend 'System.Exception' or an existing unsealed exception type instead. Do not create a new exception base type unless there is specific value in enabling the creation of a catch handler for an entire class of exceptions.