NOTE: To be able to process Internet Information Services (IIS) events, you must enable the Remote Registry service on the target computers. See Configure Infrastructure for Monitoring Windows Event Logs for more information.
To configure the Operational log size and retention method
On the computer where IIS is installed, navigate to Start → Windows Administrative Tools (Windows Server 2016 and higher) or Administrative Tools (Windows 2012) → Event Viewer.
- Navigate to Event Viewer tree → Applications and Services Logs → Microsoft → Windows and expand the IIS-Configuration node.
Right-click the Operational log and select Properties.
- Make sure Enable logging is enabled.
- Set Maximum log size to 4 GB.
- Make sure Do not overwrite events (Clear logs manually) is cleared. If selected, change the retention method to Overwrite events as needed (oldest events first).