I have the following piece of PHP code.
mail('firstname.lastname@example.org','TESTmail','this is a test');
The mail doesn't go anywhere. The person I am sending the mail to receives nothing. As far as I know my syntax is correct. I suspect it is an issue between the Linux server where the php code is run and the mail(outlook/exchange) server, but I don't even know where to start looking. There have been a lot of IP and DNS changes recently and I really suspect that that is the underlying issue, but I can't find it anywhere on the linux server.
Any ideas, or am I on the wrong track?