It's not really that strange, unfortunately. DL's never have worked as they
should and Microsoft has not seen fit to address any of these issues. Most
savvy users abandoned them long ago.
The only time I have seen DL's work consistently is if they contain only
Contacts that exist and were created in the same information store and
profile as the DL. After that, things go haywire. You can always try the
"Update Now" button in the DL. I've been searching for a user for whom it
works.

Signature
Russ Valentine
[MVP-Outlook]
>I have a strange one...we added an email address to a distribution list and
> sent an email using the list. Outlook sends an email to the users from the
[quoted text clipped - 5 lines]
> We are using OL2000.
> Thanks in advance.