Thanks for the extra details. I'd recommend creating a test script that uses the PHP mail function to send an email directly to yourself:
<?php
// the message
$msg = "First line of text\nSecond line of text";
// use wordwrap() if lines are longer than 70 characters
$msg = wordwrap($msg,70);
// send email
mail("your@email.com","My subject",$msg);?>
You'll need to replace your@email.com with your own email address in the script above.
If you don't receive the test message after running the script, it's likely that there is an issue with the server itself.
Cheers,
Greg
Greg Thomas
PHP Programmer - interactivetools.com