throwNotFoundExceptions property
Controls whether "not found exceptions" are thrown or not.
If true, the handler will thrown a NotFoundException if the file or directory could not produce a result.
If false, the handler will return null.
Its default value is true.
Normally, the application will want these exceptions to be thrown, so it can handle the missing file/directory just like any other missing resource (i.e. process it in an exception handler and generate an error page back to the client).
Implementation
bool throwNotFoundExceptions = true;