Hi We have observed a strange behaviour on one of our servers. We have 3 identical mailbox servers (Exchange 2010 SP2). All servers was installed and put into production at the same time. Outlook 2010 in online mode consumes 8-15% cpu on the client workstation when a mailbox is located on mailbox server 1. If I move a mailbox from mailbox server 1 to one of the two others cpu comsumption drops to 1%. Outlook in cache mode comsumes 1% on all three servers. Mailboxes are distributes equally between the three mailbox servers. Any ideas what could cause this behaviour? Best regards Klaus Ringe Nielsen

is it happens with one particular user or every one in the organization. get the memory utilization and other parameters on mailbox server 1 is the mailbox server 1 locates in different site for the client your taklking about also check the network connectivity from the cas array to the mb server1

Are you using public folders, and if so do you have replicas on all 3 mailbox servers?[string](0..33|%{[char][int](46+("686552495351636652556262185355647068516270555358646562655775 0645570").substring(($_*2),2))})-replace " "

Yes, we're using public folders, and all folders are replicated to all three servers.Best regards Klaus Ringe Nielsen

Hello, How about moving the problematic user to the old mailbox store? Is it will good? Thanks, Simon

Hi All users on the server is affected. When I move a user from server 1 to server 2 the problem stops. If I move the user back again the problem starts again. Best regards Klaus Ringe Nielsen

Hello, How about moving the problematic user to the old mailbox store? Is it still good? Thanks, Simon