Installation and Upgrade > Installation and Configuration Guide - Update Existing Installation > Updating an Existing Installation > Launching the PTC Solution Installer (PSI)
  
Launching the PTC Solution Installer (PSI)
The following procedure describes how to install the update:
1. Insert the PTC Solution Installer CD.
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Do not run the installer from a Windchill shell as there may be updates to the Windchill command code.
2. From your CD drive, enter the following command:
Windows
<staging_folder>\PTCSolnInstaller.01\setup.vbs LAX_VM %JAVA_HOME%\jre\bin\java.exe
UNIX
<staging_folder>/PTCSolnInstaller.01/setup LAX_VM $JAVA_HOME/jre/bin/java
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If you have configured SSL and added SSL certificates to java installed by Windchill then, to perform a update using PSI make sure you use an alternate java for PSI execution. Use the following commands:
Windows: <staging_folder>\PTCSolnInstaller.01\setup.vbs LAX_VM %JAVA_HOME%\jre\bin\java.exe
UNIX: <staging_folder>/PTCSolnInstaller.01/setup LAX_VM $JAVA_HOME/jre/bin/java where, JAVA_HOME refers to a copy of your Windchill Java which has SSL certificates in it.