Is this an exchange account on a domain or a POP3 account from your ISP? Have you tried it on another computer?
I have the same problem. In addition, it only affects content in the body of the email. Attachments or links in the subject line work fine. If I forward to another email program in my computer, ie; Hotmail or AOL, it works fine.
Are you getting a blocked url in your e-mail
Copied from http://www.slipstick.com/mail1/blocked.htm
Looking at the source, you’ll see the URL is prefixed with BLOCKED::, like this:
<A title=http://office.microsoft.com/ href=”BLOCKED::http://office.microsoft.com/“>Office Online</a>
You may be able to control it by adjusting the blocked external context setting in Outlook 2003. You’ll find these settings on the Tools, Options, Security, Change Automatic Download Settings menu or click on the Infobar of a message containing blocked content and choose Change Automatic Download Settings.
Also have a look here for Microsoft recommendation…. http://support.microsoft.com/kb/310049