We use Exchange 2000 Server and Exchange Server 5.5 together, and we've decided to roll out Exchange 2000 Conferencing Server. Can our Exchange 5.5 users participate in conferences?
Yes, Exchange 5.5 users can participate in Exchange 2000 conferences. The Microsoft article "XADM: White Paper - Installing Microsoft Exchange 2000 Conferencing Server in a Mixed Site" (http://support.microsoft.com/?kbid=326183) explains how to use Conferencing Server in a mixed site.
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