In an effort to provide enhanced capacity and service reliance, Windows Live Messenger will soon be adding an additional IP address used for PIC/Federation traffic. Some organizations have chosen to restrict this type of traffic to specific IP addresses, as referenced in Microsoft KB 897567. With this in mind we want to give you advanced notice of our intended change if you’ve configured your enterprise network in this manner. Please ensure your enterprise firewall configuration is updated with full list of Live Messenger addresses below on or before Feb 12, 2010. Live Messenger will NOT enable the additional IP addresses until on or after Feb 12, 2010 (Pacific Time) to ensure your services willn’t be disrupted by this change. IP address for Live Messenger PIC/Federation: 220.127.116.11, 18.104.22.168, 22.214.171.124 (Additional new IP address), 126.96.36.199, 188.8.131.52, 184.108.40.206.