550 5.6.0 M2MCVT.StorageError.Exception: ConversionFailedException, Content conversion internal failure.; storage error in content conversion.

Getting NDR error when sending calendar invites to remote domains.

This is what im getting.

Delivery has failed to these recipients or groups:

XXXXX@gmail.com (XXXXX@gmail.com)

The email system had a problem processing this message. It won't try to deliver this message again.

Diagnostic information for administrators:

Generating server: MAIL13-1.MYDOMAIN.TV

XXXXX@gmail.com

Remote Server returned '550 5.6.0 M2MCVT.StorageError.Exception: ConversionFailedException, Content conversion internal failure.; storage error in content conversion.'

Original message headers:

Received: from MAIL13-2.MYDOMAIN.TV (192.168.1.249) by MAIL13-1.MYDOMAIN.TV

(192.168.1.2) with Microsoft SMTP Server (TLS) id 15.0.1130.7; Wed, 30 Mar

2016 09:13:39 +0300

Received: from MAIL13-2.MYDOMAIN.TV ([192.168.9.2]) by MAIL13-2.MYDOMAIN.TV

([192.168.9.2]) with mapi id 15.00.1130.005; Wed, 30 Mar 2016 09:13:40 +0300

Content-Type: application/ms-tnef; name="winmail.dat"

Content-Transfer-Encoding: binary

From: Zvi Alikyan <ME@MYDOMAIN.TV>

To: "XXXXXX@gmail.com" <XXXXXX@gmail.com>

Subject: Test

Thread-Topic: Test

Thread-Index: AQHRiktN78yXWl6zgkCVtVVsFQbphg==

Date: Wed, 30 Mar 2016 09:13:39 +0300

Message-ID: <7262F7DF-2578-4396-9CE3-59718DE8B915@MYDOMAIN.tv>

Accept-Language: en-US

Content-Language: en-US

X-MS-Has-Attach: yes

X-MS-TNEF-Correlator: <7262F7DF-2578-4396-9CE3-XXXXXXXXX@MYDOAMIN.tv>

MIME-Version: 1.0

X-MS-Exchange-Transport-FromEntityHeader: Hosted

Return-Path: ME@MYDOMAIN.tv

It working when i enable TNEF to true ( Set-RemoteDomain -Identity default -TNEFEnabled $true ) but the problem is when you leave it enabled, all emails that employees send to remote domains they got it in old RTF ugly format and not HTML format, this feature not a solution for us, so i turned it off.

We have exchange 2013 cu10, and latest ios 9.3.

I also tested this with 3rd party app (outlook app) after i install it on the iphone and try to send calendar invite from the outlook app i didn't get any NDR error, it send successfully.

And its point only to your default calendar app.

This is only happens from iPhone, our employees start to complaint about this issue!.

Please fix this,

We Need A solution or a fix to this issue.

Thank

Best Regard

Tzvi Alikyan

IT Department

Channel 10 LTD Israel