Ticket : Emails bouncing back and email limits #3QFAOO-12FO

Hi. I have an old site that I have just moved to siteground and we are finding that some emails are bouncing back. We know the email address is correct because we can send with normal email. It seems to be specific domains, like slingshot.co.nz or nowmail.com It is coming back with Unrouteable address. I'll insert the email at the bottom. We are using jNews Core 7.6.1 on Joomla 2.5.28, php 5.3.29
Using Sendmail.
The domain is hosted at webdrive which is where the emails addresses are handled but the web traffic is pointed to siteground.
Also, siteground has a limit of 400 emails per hour which is a pain. Would it work if I set up an smtp address on the webdrive server and then set that up in Jnews? or would I still be stuck with 400 an hour?
Thanks for your help.
Andrew

PS. Here's an email that was returned.
From: Mail Delivery System <[email protected]>
Date: 10 February 2016 at 22:51
Subject: Mail delivery failed: returning message to sender
To: [email protected]



This message was created automatically by mail delivery software.

A message that you sent could not be delivered to one or more of its
recipients. This is a permanent error. The following address(es) failed:

[email protected]
Unrouteable address

This is a copy of the message, including all the headers.

The body of the message is 177513 characters long; only the first

106496 or so are included here.

Return-path: <[email protected]>
Received: from ns1.sgp3.siteground.asia ([119.81.1.69] helo=serv01.sgp3.siteground.asia)
by se2.mailspamprotection.com with esmtps (TLSv1.2:DHE-RSA-AES256-SHA:256)
(Exim 4.85)
(envelope-from <[email protected]>)
id 1aTRQd-0003EB-SR
for [email protected]; Wed, 10 Feb 2016 03:51:51 -0600
Received: from localhost ([127.0.0.1]:57435 helo=serv01.sgp3.siteground.asia)
by serv01.sgp3.siteground.asia with smtp (Exim 4.80.1)
(envelope-from <[email protected]>)
id 1aTRQW-0000Y2-3L
for [email protected]; Wed, 10 Feb 2016 03:51:12 -0600
Date: Wed, 10 Feb 2016 03:51:12 -0600
To: Matthew Bickers <[email protected]>
From: Ramblers Cycling Club <[email protected]>
Reply-To: Ramblers Cycling Club <[email protected]>
Subject: 10th February 2016: Ramblers eNews... powered by Heretaunga Building Society
Message-ID: <[email protected]>
X-Priority: 3
X-Mailer: PHPMailer 5.2.1 (http://code.google.com/a/apache-extras.org/p/phpmailer/)
MIME-Version: 1.0
Content-Type: multipart/related;
boundary="b1_4432f0d11486ac7130159584b2aa7f0b"
X-Filter-ID: s0sct1PQhAABKnZB5plbIcdOATh9eiv6F9lhtnCOVq27D5f9EHsfDCcQBmj5de2Bx5YB+7NnUQEm
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X-Report-Abuse-To: [email protected]
X-Filter-Fingerprint: IFrWXGses7OKB5S5G8/dJXhXyDRoOQM5J3kcUr0HrMtA3cTUQ1R++keuE7RDJ8Kg3RbMLUalw1oC
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X-Originating-IP: 119.81.1.69
X-SpamExperts-Domain: sgp3.siteground.asia
X-SpamExperts-Username: 119.81.1.69
Authentication-Results: mailspamprotection.com; auth=pass [email protected]
X-SpamExperts-Outgoing-Class: ham
X-SpamExperts-Outgoing-Evidence: Combined (0.26)
X-Recommended-Action: accept


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