Blank message body when sending or receiving HTML formated emails Exchange 2010

Question

I Have just installed Exchange Server 2010 over the weekend on a customers system.  All clients using either Outlook 2003 or 2007 are unable to see any text in the body of emails that are formatted in HTML.  If they receive an email formatted as HTML there is no body text, if they send an Plain Text formatted email the recipient sees the text in the body.  This problem presents across all Exchange users and affects all HTML formatted emails sent or received since transitioning from Exchange 2007 to 2010.  Plain Text and Rich Text email present with no issues. If we import old email via a pst they afre able to see all email text both HTML and plain text. when we access the clients email account via OWA all emails work but then if we go into outlook 2003/2007 and click the email it removes the body text from the email in both the client and OWA have tried Outlook connection issues with Exchange 2010 mailboxes due to RPC encryption requirement
 http://support.microsoft.com/default.aspx/kb/2006508 and it made no difference at all.
Thanks
Update: Have just tested further and all pc seem to work ok with either 2003 or outlook 2007 on.  The problem only seems to be happening on the remothe desktop services server which has outlook 2007 ( have also tried outlook 2003 with same results)

Answer 1

We have just migrated to Exchange 2010 and have had some blank emails come in to our system.  We think we have a reason and fix for
it. Hopefully this helps someone else…
Staffs have their own private mailbox (as you would expect) but also share common mailboxes like "Support" and "Info". When an email came
into the inbox on a shared mailbox, it might be blank. Plain text emails seemed to be okay. 
We found that when an email came in, it was readable for about two or three seconds (you need to be setup to send a test and check the inbox quickly - we used Outlook 2007 with the reading pane turned on) and then it blanked out!. We checked the incoming
email by using the arrow keys to select it and then select the email below the new email, if you go back and forth between them you can see the good new email suddenly goes blank.
So send another test, but this time make sure the email is set to “Plain Text”. Our email turned up fine, two seconds latter
it had a NOD32 signature appended to the end of it saying that it had been scanned by NOD32 (you may have seen this kind of note appended to the end of emails before).
What appeared to be happening is that one or more users sitting at their desks in Outlook had different settings configured in NOD32 (they
were supposed to be using the server based profile that we control). We thought we had the server doing the AV work, but several of our client PCs had NOD32 enabled to integrate with Outlook. New items received in the shared Inbox’s were being scanned
by the client PCs and having a signature appended which was mucking up the HTML format of the email and Exchange 2010 blanked them out.
Make sure your AV products aren’t corrupting the email formats causing them to be displayed blank. Try tests using OWA only and don't
access the mailbox using Outlook.
Thanks.