trouble with phpmailer using smtp on windows

Hi guys,

I have been trying to setup an enquiry form on a windows server running php and IIS on windows.

I am using smtp and phpmailer to send the mail.
This works fine when I send a mail to my smtp mailer server on my server.

$mail->Username = “[email protected]“;
$mail->Password = “mypassword”;
$mail->Host = “mail.mysmtp.com.au”;
$mail->Mailer = “smtp”;

But when I switch it to my clients smtp server it fails.

$mail->Username = “[email protected]“;
$mail->Password = “clientpassword”;
$mail->Host = “mail.clientsmtp.com.au”;
$mail->Mailer = “smtp”;

It like my clients server can’t email to itself.
I tryed changing

$mail->Host = “mail.clientsmtp.com.au”;

to

$mail->Host = “localhost”;

but that did not work either

Thank you in advance for any advice

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