Good Morning,

Last month we migrated from Exchange 2007 to Exchange 2013. From time to time, but mostly in the morning the server has a 100% cpu use. And then every outlook client gets disconnected.  And we have absolutely no clue where it's from.  

sometimes the system process or RPCClientAccesServices or noderunner has a high cpu, 

I know that exchange 2007 had a tool Exmon but it's not working with exchange 2013. Is there a similar tool to check this? And what can we check why this is happening?

Specs.
It's running on vmware Esxi 5.5
windows server 2012r2
32Gb ram
4 CPU core
11 databases 
900 mailboxes 
1 database for public folders

Hi Jeroen..

To use Exmon you first need to download Experfwiz on your Exchange server 2013. 

You can download this PowerShell Script from the link given below: -

https://experfwiz.codeplex.com

Thanks

Joe

Joe,

Thanks for that.

Other question yesterday we've had some trouble (100% cpu for like 30 min) so we did a reboot, and since than the imap is not working anymore... 
When i do a telnet session to the server i get the message "connection to host lost"

When i do get-healthreport i see that the IMAP.Proxy is offline could that cause the problem?

Hi..

Just check out the link. Hope it will work for you

https://technet.microsoft.com/en-us/library/ms.exch.scom.imap(v=exchg.150).aspx

Thanks

Joe