You put all of the intended receivers into the Outlook address book, and have Outlook forward to all of them when it gets a message from your leader. That does make you responsible for keeping the addresses current, though.
You would need to set filters in Outlook, and create a list of addresses from the address book. The filter takes incoming mail to your special address, looks at the “Subject” line to see that it is intended for your organization (“Subject”=“Organization Newsletter”) and then forward to all of the people in the address list you put into the filter.
Keeping the address list is the thing that will be the real problem. By doing it the way you’ve specified, you will have to update the addresses in your address book - which you group’s leader already does for himself, anyway.
Are you on DSL or cable? If so, you might consider doing things differently. You would need a competent system administrator to set it up for you, though.
For stability, I’d install Linux on the spare PC. Most Linux distributions come with a mail server. An older version that you can get for free off of some magazin will do as well as a newer version - there will be some bugs in it, but you are still better off than using Microsoft.
Set up the mail server (usually Sendmail, though it might be Postfix) to only accept mail from users that you specify. Make them have to give a password to send mail through your server - this is to stop spammers. This server can either pass them on to your ISPs SMTP server or send them out itself.
If you are on DSL, you may or may not have a permanent IP address. If not, you can setup and account with DynDNS and some software on your Linux machine that will keep your IP address up to date on a name server in the internet. You can setup some kind of reasonable name there for free - the free ones include DynDNS in the name, but so what. This way, your group leader sends his mail (with all of the BCCs) to your server (he puts “gotpasswords.DynDNS.com” into his SMTP server field in his mail program.)
If you are one of the lucky folks who has a permanent IP address that can be reached from the rest of the internet, then your group leader just puts your IP address into the SMTP server field of his email program, and he’s in business.
If you are on DSL with a router providing service to both your PCs, you’ll probably have to do a little jiggery-pokery with the settings on it to get the SMTP port (25 is the standard port number)
Once you’ve got things setup, you can pretty much just ignore it. The group leader keeps his addresses up to date, and he doesn’t bother you with it. You keep your server running 24/7 and update the software once in a while. The technical aspect is rather more complicated than having Outlook forward things for you, but you don’t get involved with keeping the address book current.
Thinking about things, though, it seems it’d just be easier to get the boss an account at your ISP and let him send things through there. He’d probably need a new e-mail program, but then he’d need that to use your server (if you aren’t just doing forwarding with Outlook.)
Anyway, my two cents. Its just how I would do it if I had DSL.
BTW:If you are on dial-up, then forget all of the complicated stuff and just use Outlook to forward.