Everyone, Thanks ahead for any input. Our setup is this... ISA box, uses internal DNS that resolves to ISP DNS servers. This because we are on AD domain. Internal OWA Exchange 2000 server. We have DNS'd the Exchange server so internally you will resolve to the internal address, and externally will resolve to external address. The problem: ISA is on one Windows 2000 AD tree, Exchange on a separate one. The login on IE on this setup resolves back and forth between logging into ISA and the Exchange server and just keeps prompting. Any ideas? Tx! GReg