Indexing rules tell Perceptive Search which folders and files to index, and what criteria (if any) to apply to particular files and folders. The Indexing Wizard applies very basic indexing rules to each of the folders it processes. By setting up indexing rules manually, you can gain greater control over how Perceptive Search treats different file types.
To modify the file rules of an index, select:
Index > Content Sources and click on File Rules
Select the folder or file for which you would like to create an indexing rule.
Click Next to enter the options for the rule.