hi.. thanks for the time. i am having some issues in regards to our Exchange 2007 server. in the event viewer there are lots of logs in regards to 'Exchange Availability Service' and 'mapi session exceeded half of the maximum of 16 objects of type 'session''... and 'there are 20 rpc requests that take abnormally long time to complete.' ... These seem to all indicate an RPC issue... and just after this the mailbox server becomes unavailable and we had to restart the server. I was wondering if someone can help point us in the right direction. With the Exchange Availability Service: Time in User Mode: 180832 ms. Time in Kernel Mode: 4915 ms. RPC Operations: 950849. Shouldnt it be under 50ms? I will run an exBPA tomorrow morning to see if anything else comes up. And should I open the mapi sessions to unlimited? http://maxurmail.blogspot.com/2011_03_01_archive.html Thanks again.

Hello, You can use Exmon tool to check the RPC client sessions from each Outlook client side. After finding some problematic users, you can first check whether they installed any third-party search tools, or you can run them in Outlooks safe mode and see if their behaviors are back to normal. Thanks, Simon