Try rebuilding the index.
Try a new profile.

--
Russ Valentine
[MVP-Outlook]
"AlecR" wrote in message
...
I am running Office 2007 on a PC with Vista Ultmate.

When I use the quick search in Outlook Contacts, it very often doesn't
show
names that I find by browsing through the list. I have checked the
indexing
status, and it says completed.

I also get an intermittent error when closing a search by clicking on the
X
in the "search contacts" box.
Message says "The messaging interface has returned an unknown error'. ...

When I close the error message, Outlook works OK. Just the message is
annoying.
Any suggestions welcome.
Thanks in advance.