Changing the number of days audit trails to keep

First click 'Management'

Then 'Occasional Menu'

 

 

Then 'Options'

 

Then the 'Security' tab at the top right.

 

 

The option for the number of audit trails to keep is on the right about 3/4 of the way down. Setting it to 0 will keep the audit trails forever and any other number will keep them for that number of days.