OWA / ActiveSync logs

To configure IIS logging for Exchange, start “Internet Information Services (IIS) Manager” (Server Manager or Administrative tools) and select Logs. You can turn on logging on specific directories only, i.e. OWA or Active Sync. Before doing any changes on the logging for the directories, you need to have the logging enabled on the Site level. After making the changes, you can turn off the logging on the Site again.

The IIS Logging does not purge logs, you need to create your own script and use scheduled tasks. There is an option for “Log File Rollover”, but you can not limit the total amount of data or logs. A good idea is to keep the IIS logs on a separate volume in-case the disks fill up.