this is from QMC help online, system -->setup --> management service
On the Auditing tab, it is possible to manage the settings of the tracking of changes on tasks and settings made by users in the system. The audit log stores information about the users, the changes, and the time stamp.
This check box indicates whether the audit logging is turned on (ticked) or off (unticked).
Note! It is not possible to enable the audit logging on this tab, but auditing must be turned on in the Management Service configuration file, QVManagementService.exe.config, found in the directory C:\Program Files\QlikView\Management Service. Changing any of the parameter values requires a restart of the QlikView Management Service (QMS).
The full absolute path for the audit logs.
Days to Keep Audit Logs
The number of days that the audit logs are saved. Logs older than this setting are overwritten by new logs.