Install OneCare (the trial) on the new PC from
http://onecare.live.com and activate it with your subscription LiveID by clicking subscribe.
Optionally, make on of the 3 existing computers a Hub PC in your Circle and view the subscribed PCs. The one that is no longer alive will be listed and will show the lasted communication date/time. There is a link next to each PC - remove this PC. Select the "dead" PC by clicking the link to remove and it will be off your subscription. Unless you are doing a while lot of reinstalling, this last bit is optional. Simply adding OneCare on the new PC and activating will take care of it as far as licensing is concerned.
-steve
Microsoft MVP Windows Live / Windows Live OneCare, Live Mesh, & MS Security Essentials Forums Moderator
