Error: attached files in "winmail.dat" format"

Attached files in the winmail.dat format don't depend in any case on the incoming or outgooing e-mail service providers. This is an issue specific to Microsoft, as they mention on their support website: http://support.microsoft.com/kb/278061/fr

The most recent help on the subject can be found here:
http://www.slipstick.com/problems/outlook-is-sending-winmail-dat-attachments/

You will learn how to solve the problem either with the help of internal settings within the different versions of Outlook, or with the help of third-party software allowing you to read winmail.dat contents.

Illustrated steps

How to stop sending rich text format e-mails with Outlook

More information

We recommend using another email program to avoid these attachement problems.