To set your mail server, it's the
SMTP = localhost
line you need to change. A lot of new commers to PHP think that when they use PHP to send email that it just manages to send it, using their already set up email client such as outlook or thunderbird or whatever is being used.
The fact of the matter is it does not.
In fact, as i mentioned previously on a windows platform if there is no outgoing SMTP server available, then php's mail functions will just silently die and not give any indication as to a problem, other than the fact the mail does not get sent.
Under linux, the situation is slightly different. If an SMTP server is defined, then PHP will try to use that, and if not of connection to the server fails then it will fall back to the unix/linux sendmail method of sending.
What this means, is that if your sending to local recipients on the same machine then under linux your mail will always be delivered, it just will not get delivered to the outside world, well at least not unless you have a correctly set up send mail that can send to the outside world.
Under windows, even local delivery will fail without an SMTP server.
The value you need to add to the
SMTP = localhost
line, depends on how you access your email, in general you'll probably want to put the address of your internet providers outgoing email server in here, and this will likley be the same address you have in your email client account setup, or as defined in your ISP's documentation.
You could in theory also point the SMTP server to gmail, if you have a gmail account, but thats quite difficult to set up beacuse you've got to start setting up SSL and other things.
If you have windows XP professional, or Vista professional, you may also want to explore the added software on your install CD, along with a copy of IIS web server, there is also an smtp server, which allows you to send email localy, but unfortunately not access it to read it from an email program, it does work quite well for testing though.
Your last option, if you have the skill or know someone that does is to build your own Linux server and set up an SMTP server on there, then point to that.
There you have a number of options from easy to hard. :-)
Hope that gives you some background to explore, i can't explain exactly how to do it beacuse i don't know what set up you have or how your existing email client works.
Cheers
Shawty