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%\bin\java.exe
UNIX
<staging_folder>/PTCSolnInstaller.01/setup LAX_VM $JAVA_HOME/bin/java
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If you have configured SSL and added SSL certificates to java installed by Windchill then, to perform an 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%\bin\java.exe
UNIX: <staging_folder>/PTCSolnInstaller.01/setup LAX_VM $JAVA_HOME/bin/java where, JAVA_HOME refers to a copy of your Windchill Java which has SSL certificates in it.