free busy not avaialble for outlook 2003 users for cross forest senario.


  • Dear All,

    I just setup free busy between two forests of exchange (2007 and 2010) and it is working fine for all outlook 2007/10 users. I have a scenario, my exchange 2010 forest have some outlook 2003 user who are not able to see free busy of exchange 2007 users. please note that I have just configured the availability address and nothing else.

    I was learnt from that outlook 2003 user will be able see free busy of exchange 2007 users by below process.

    1. An Exchange 2010 user using Outlook 2003 request free/busy information for an Exchange user in the Exchange 2007 forest.
    • 2. Outlook 2003 connects to the “SCHEDULE+ FREE BUSY” system  folder in a public folder database in the Exchange 2010 forest.
    • 3. The RPC Client Access service on an Exchange 2010 server intercepts the free/busy request and sends it to the Availability service on an Exchange 2007 Client Access server in the Exchange 2007 forest.
    • 4. The Exchange 2007 CAS server retrieves the free/busy information in the respective mailbox and returns it to the RPC Client Access service in the Exchange 2010 forest.

    Satpal Kataria

    Sunday, October 06, 2013 8:29 PM


  • That makes sense since Outlook 2003 doesn't use the availability service, it gets its free-busy data from the system public folders.  I recommend that you upgrade Outlook, or consider synchronizing the free-busy public folders between the organizations using something like the InterOrg Replication Tool.  I believe Quest Software also has a tool, at least they did a few years ago.

    Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."

    Monday, October 07, 2013 6:18 AM