We are also experiencing this problem (details below).
We upgraded from Office 2003 Professional (no patches) to Office 2003 SP1
including all post-SP1 hotifxes over this weekend. This problem only started
appearing yesterday (Monday), which means that this is a serious bug within
one of the Office 2003 updates released. For your information, we are also
running Windows XP SP2 with all the latest updates on the desktop, and
Windows 2003 with Exchange 2003 SP1 on the server, with no Exchange or
Outlook addins.
Per Jeff Stephenson's suggestion, I disabled the Anti-virus software
(Symantec) from scanning MS Exchange on the client. Unfortunately however,
this did not fix the problem.
The problem is as follows:
Only on certain email address domains (ie: emails sent to any address within
that domain), when you send an email to that address, the To: field is blank
when you view the sent email in the Outlook 2003 Sent Items List and open the
Sent email for viewing. However, this does not affect the email's delivery -
only it's view in Outlook - we have confirmed with the recipients that the
emails are in fact being received.
I have noticed the following:
1. If you send an email to multiple e-mail domains in the To: field, having
this one problematic email address will cause the entire To: field to be
empty. However, on this same email when multiple cc: addresses are entered,
again with the problematic email address entered, the other cc: email
addresses will show, however the problematic one will not.
2. If you perform a "reply-to-all" on this sent email, the email addresseses
appear in the To: field.
3. One googled message thread mentioned that deleting the NK2 file
temporarily fixed this problem.
Any help or advise would be appreciated. As you can see from the microsoft
newsgroups and google searches, this appears to be a serious bug with is
affecting a large number of Microsoft Outlook installations.