General

Truncate text after question marks (?) in referrer URLs - truncate parameters of scripts that are placed after questions marks

Truncate text after sharps (#) in referrer URLs - remove anchor names (that are placed after # character) from referrer URLs

Truncate text after question marks (?) in file names - truncate parameters of scripts requested on your site

Show internal visitor referrers (referrers from the analyzed site) - if this option is set referrers that are URLs from the analyzed site will be shown in referrer list

Show search engines in referrers - show referrers recognized as search engines in the lists of referring sites and referring URLs

Convert file names to lower case when analyzing IIS logs - this option can be useful if you analyze IIS logs and your visitors request files with different character cases e.g. Index.htm and index.htm. IIS usually works with file systems (FAT or NTFS) that have case insensitive file names.

Convert user names to lower case when analyzing IIS logs - use this option to convert authenticated user names to lower case when you analyze IIS logs

Count spiders as visitors - process requests from spiders the same way as requests from visitors. You can find more information on analyzing spider activity here.

Show 3D charts in reports - show 3D style charts in the report

Smooth charts in HTML reports - smoothed charts look better but are larger and generated slower.
Note: chart smoothing isn't supported when the program runs from the scheduler under Windows Vista/2008/7 or later.

Use multiple processors (if available) - if this option is set and the program is running on a multiprocessor or multicore system, multithreaded analysis will be used to take advantage of multiple processors/cores.

Disable host reporting to reduce memory usage - disable the Visitors > Hosts table even if it is checked in the report contents settings. This option also hides the "Total Unique IPs" value in the General Statistics > Summary table as it is still necessary to create a list of hosts to show this information. Checking the option can significantly reduce memory usage for analysis of large sets of log files.
Note: this option doesn't affect other tables and charts that show information on hosts.

Use adaptive session timeout for very high traffic sites - this option is useful if you analyze log files of sites with more than approximately one million hits per hour during peak hours if the default visitor session timeout (30 minutes) is set. Such log files cannot be processed unless the session timeout is reduced manually or the adaptive timeout is used. When this options is enabled, the program automatically reduces the session timeout during peak hours to reduce number of simultaneous visitors and so amount of memory required to analyze the logs. However, using this setting may increase number of visitors shown for the peak hours.

Visitor session timeout - timeout value used for determining visitors