This KB will show you how to enable Throttling logging for Exchange Server 2013 Throttling Policy.
Open folder:
C:\Program Files\Microsoft\Exchange Server\V15\Bin
Open the configuration file:
Microsoft.Exchange.RpcClientAccess.Service.exe.config
Add the word Throttling to the line below:
<add key=”LoggingTag” value=”ConnectDisconnect, Logon, Failures, ApplicationData, Warnings” />
Line should look like this:
<add key=”LoggingTag” value=”ConnectDisconnect, Logon, Failures, ApplicationData, Warnings, Throttling” />
Restart the Microsoft Exchange RPC client access server
To search the log file for Throttling events open the log files and search for
Connection Limit Exceeded
The logs located at:
%ExchangeInstallDir%\Logging\RPC Client Access\