I have a problem when adding new contacts to a shared contact list.  The
newe contact disappeared shortly after it showed up on the contact list.

I have a user who have access to one of our executives contact list.  Her
access priviledges include create, modify, and read.  She was able to add
new contacts there before.  But now, everytime when she attempts to add a
new contact, that new contact will show up briefly in our executive's
contact list and disappear aftward.

I looked through all the Microsoft Knowledge Base and google newsgroup but
stuck with no resolution.  Have anyone encounter a similar situation?  If
so, how do you come about fixing the problem?

Settings:  User is running Windows XP Pro with Outlook 2000 email client.
Our email server is still running on Exchange 5.5.

Thanks.