Hi, You can only accomplish this by using a third party product. You can evaluate Co-Standby Server or Replistor from Legato Systems. Both products offer WAN capabilities with automatic failover. I've also heard of similar products from different vendors, but I can not give you names now. One other consideration for this scenario is to direct your users (clients) to the second exchange machine in case of a disaster. You may need to change DNS or WINS records or even change routing tables. Hope this helps, ILKER