Question : Permitting internal and outgoing HTML and Rich text in Exchange but converting incoming (external) HTML emails to plain text.

Hello folks; I have 5 Exchange 2003 servers and I would like to know if it is possible to permit HTML or Exchange Rich Text messages to be transmitted amongst employees and to our external clients but convert incoming HTML external domain messages to plain text?

Answer : Permitting internal and outgoing HTML and Rich text in Exchange but converting incoming (external) HTML emails to plain text.

Not natively, however you might be able to achieve this by writing a custom SMTP transport sink that processes all inbound email and strips the HTML tags from them.

The following will give you the basics for creating a custom SMTP transport sink, from there you will have to look at how to incorporate the functions for converting the inbound HTML to text whilst still retaining as much of the formatting as possible

SMTP Server Transport Events - Simple Scripting
http://www.codeproject.com/KB/IP/smtpevents.aspx

How to write an OnArrival-type SMTP event sink in managed code by using Visual Studio .NET 2003
http://kbalertz.com/894286/write-event-managed-using-Visual-Studio.aspx