The first setting gives you the ability to limit sharing with external users via their domain (that is, abccompany.com). You can allow or block external sharing from these domains. This can be particularly useful if you only have a certain set of other organizations that you work with and if that list doesn't change often. If the list changes frequently, this setting can become a nuisance:
If you add a domain to be blocked, none of your users will be able to share with anyone from that domain.
We recommend setting the next two settings for increased security:
This set of settings does not apply to anonymous ...
