Mail not displaying message when opened by Windows computers

Question

I am sending out emails to clients with an attachment.Then in the mail field I write a summary as bullet points. My Microsoft clients receive the attachment but no message un the mail field.

Answer 1

Simular problem:
Its iMail Version 6.3 (1503) which comes with a fresh install of 10.8.3.
Any email base64 encoded is corrupted or not shown.
eg Any message from and Exchange Client that has both plain text and html in the same message where the plain text section is Base64 encoded.
eg
Content-Type: multipart/alternative;
     boundary="_000_CD848A046C8D3_"
MIME-Version: 1.0
--_000_CD848A046C8D3_
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: base64
base 64 encoded block
-_000_CD848A046C8D3_
Content-Type: text/html; charset="utf-8"
Content-Transfer-Encoding: base64
base 64 encoded block
The work arround it to switch to the classic view, open the message there, then switch back to the modern view and the text of the message magically appears. Its probably something to do with the way in which the new iMail processes message bodies, that the older style viewer had fixed. (You can switch between classic view and modern view under the Vieweing preferences tab)
It also seems to impact sent messages or anything thats been base64 encoded.
Hopefully its such a major bug it will be fixed soon. (lol, like some of the bugs in iMail on 10.6.8 were fixed ?)