RTF (TNEF) messages handling
If e-mail messages are sent outside the organization in RTF (to be more precise in TNEF - Transport Neutral Encapsulation Format), a disclaimer is added only to the MIME part that is a representation of the message in the plain text format. Usually messages in TNEF consist of the "text/plain" MIME part type that contains a text of the message in a plain text format and an "application/ms-tnef" part that contains the "winmail.dat" attachment, representing the message in the original RTF. If the recipient of the message sent in RTF uses Microsoft Outlook, s/he will see the message in its original RTF format without the disclaimer. However, if he uses another e-mail client, s/he will see a representation of the message in the plain text format with the disclaimer added by the CodeTwo Exchange Rules program.E-mails are sent outside the organization in the RTF format very rarely. If a user writes an RTF message in Outlook and sends it to an external address, Outlook will transform it to HTML by default (although the option may be disabled to prevent Outlook from converting the message format) and a disclaimer will be added to such a message.
If as an administrator you want to make sure that messages in RTF are never sent outside via Exchange Server, take the following steps:
| 1. | Run the Exchange System Manager program. |
| 2. | In the left panel go to Global Settings | Internet Message Formats | Standard. |
| 3. | In the context menu choose Properties and go to the Advanced tab. |
| 4. | Set the Exchange rich-text format option into Never use (Fig.1). |
After configuring the Exchange server in this way, messages sent by users in RTF will be converted into HTML by the server.
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| Fig.1. Exchange server configuration preventing sending messages in the RTF format. RTF messages will be converted to HTML by the server. |