E-mail is being converted to plain text

I hope go GOD this is the right place to post this question, frankly I’m getting sick of posting it and being told it’s in the wrong place.

The problem I’m encountering is: I have a traveling user connecting to our mail server from the internet to send e-mail as if he’s actually on our network. I’m guessing this is fairly normal, considering he did it at his previous place of employment. Every e-mail he sends is being converted to plain text. But the format of the e-mail is still technically HTML. On the Format menu in Outlook “HTML” is checked.

We’re running Windows 2000 server and Exchange 5.5 for e-mail.

This guy is our sales and marketing manager. He wants to have pretty-looking e-mails to impress clients. Plain text e-mails don’t look very pretty, they’re down right ugly.

PLEASE help me out here. I can’t figure this out!

Thanks
-Brian