Installation und Upgrade > Installations- und Konfigurationshandbuch - Vorhandene Installation aktualisieren > Updating an Existing Installation > Preparing to Update the Installation
  
Preparing to Update the Installation
To prepare for the update, read and understand the updates contained in the release and determine how they will affect your systems. This includes not only what steps must be performed to install the updates, but how the updates may affect configurations, site-modified files, and customizations as well as end users. Update information is located in the following places:
Maintenance Release Documents
Update Advisor Tool—For a list of the customer SPRs fixed in this maintenance release, use the Update Advisor tool, available here: http://www.ptc.com/appserver/cs/update_advisor/update_advisor.jsp
Windchill Maintenance Read This First—Identifies the manual installation instructions to complete each maintenance release.
Installation instructions for the update are described in Launching the PTC Solution Installer (PSI) -- provides the details for installing the updates that are in the maintenance release or service pack.
Major Release Documents
Windchill Read This First—Identifies the manual installation instructions to complete the point release that did not make final documentation. This also identifies new features that are a part of the point release.
Installation instructions for the update are as described in Updating an Existing Installation—Provides the details for installing the updates that are in the point release.
Maintenance updates are cumulative. This means that once a correction has been delivered in one version of the update, it will be included in all future versions of the Windchill Service Pack for that release. (Each version of the Windchill Service Pack is identified with a different datecode).
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Before attempting to access any part of the Windchill system ensure that all installation procedures have been completed.