Installation and Upgrade > Installation and Configuration Guide - Update Existing Installation > Updating an Existing Installation > Defining Settings
  
Defining Settings
In the Define Settings step PSI uses the existing web configurations for HTTP Server and Servlet Engine by default. You can choose not to use the existing web configurations by deselecting the Preserve HTTP Server configuration files option.
If you opt to preserve your existing web configurations, then you need to update the HTTP Server configuration files manually for the latest updates to be reflected in your Windchill system. For more information, see the section "Updating the HTTP Server configuration files" in Post-Update Actions.