"more secure" 3rd-party file sharing?

[Ben Scott]

On 8/23/06, Bruce Dawson <jbd at codemeta.com> wrote:
> Yes. It was a pain. It sent an email to all "unrecognized" senders ...

  I believe the OP is looking to guard against inadvertent disclosure
via people inside the organization sending things outside the
organization.  OP is not looking to filter inbound attachments (not on
this thread, anyway).

-- Ben