Downloaded the whole existing site.
Added local config

[for my computer; should work for all XAMPP installations]
Updated config

Yeah. That's it. What other options are there I wonder?
Fixed two errors. Messages should work now!

I saw the Post_Message coding mistake before... Tidor (or whoever
originally wrote this) wasn't resetting the bcc-list to emptystring
after hitting the ceiling of bcc... we've never had problems until this
year b/c we had less than 80 on the list... I fixed it earlier this year
but forgot... and restoring the backup made it come back. yeah.
I lied. Mailing should work *now*

I can't test it on my computer though since it doesn't send emails from
localhost.

Also, added: "View" on sent message, updated some outdated code
"session_unregister()", allowed sending to yourself, attempted but now
commented out a different way of mailing.