Hi We are running Exchange 2007 SP1 and Outlook 2007 clients (on the whole, but there are some Outlook 2003 clients still left). I had some questions regarding Free/Busy I was hoping someone could help me with. 1) Would I be correct in saying that only users in my Exchange org can see each other's Free/Busy? This feature is not available for users with mailboxes outside the org? 2) I understand in Exchange 2003, F/B info was held in a Public Folder, but with Exchange 2007, it is held in the User's mailbox but accessed via the CAS server - is this correct? 3) Since we have both 2003 and 2007 clients, would I be correct in saying that there is still a Public Folder that holds F/B info, but only Outlook 2003 clients use it? 4) When all clients are using Outlook 2007, what will happen to this PF? Thanks!

Hi,About your questions: 1) Yep this is correct if there is no trust and information is exchanged between the forests users from external forests won't be able to see it. If you want this have a look at Exchange 2010 which will have this option 2) A sort of the CAS delivers the availability service which will provide a direct look of the f/b info of the user 3) I am not 100% sure if this is true because Outlook 2007 still can use the F/B info. In previous versions the client needed to publish the info in the F/B PF so other users could see it. So I suspect that if a PF exists Exchange 2007 will use it also.4) You won't need it anymore for F/B but might need to keep it in place because other information is stored in there.The Exchange Product team has written a nice blog about Free/Busy and PF which is worth reading:http://msexchangeteam.com/archive/2006/08/04/428597.aspxRegards,JohanExchange-blog: www.johanveldhuis.nl