PROBLEM : My “Contact Form” in Drupal (v6.14) was not delivering any email to my mailbox. No error was indicated in Drupal logs.
SOLUTION : Turned out my web hosting company had to move my domain name record from /etc/localdomains to /etc/remotedomains.
Here’s a php script to test the sending of email:
$to = "firstname.lastname@example.org";
$subject = "Test mail";
$message = "Hello! This is a test message.";
$from = "<name>@<your domain>";
$headers = "From: $from";
echo "Mail Sent.";