OWA providing credentials multiple times

[SNosko]

When I try to view my Inbox by using Microsoft Outlook Web
Access (OWA), I am prompted to provide my logon
credentials several times before the Inbox appears.

I've looked at Q-Article Q327349 but it does not apply to
me. I don't have either Micrsoft Small Business Server
(SBS) 2000 or Internet Security and Acceleration (ISA)
Server 2000.

I'm running Windows 2000 Server with SP4 and Exchange 2000
with SP3.