Installazione e aggiornamento > Installation and Configuration Guide > Troubleshooting > The PTC Solution Installer Global Registry
  
The PTC Solution Installer Global Registry
The PTC Solution Installer (PSI) creates a global registry file for each installation. The global registry file is needed to update an installation, so the PSI automatically backs it up into the local installation every time the PSI is executed.
The registries for each installation are created under whichever user they installed as. For instance, if someone ran the PSI as “root” on UNIX, the PSI creates a registry for the installation under root's home directory. This prevents other users from seeing or modifying root's installations via the PSI; but if the registry is removed, not even root will be able to see them.
The registries are created here:
UNIX
<user_home>/ .ptc/windchill/<instance_id>
Windows
<drive>\User Profiles\<user_name>\Application Data\PTC\ Windchill\<instance_id>
Within the <instance_id> is the actual registry file “psi_iir.xml” which contains information about that instance. There may be some numbered backups such as “psi_iir.000.xml” as well.
The <instance_id> folder is a computer-generated unique ID, so in order to identify a particular registry, the psi_iir.xml must be referenced.
When the PSI is executed, the registry is backed up to the following location:
<Base Installation Directory>/PSI//installer/instreg/<instance_id>
where:
<Base Installation Directory> = the base common directory of the installed products
<instance_id> = the unique string that identifies the registry instance
The base installation directory and its instance_id are added to a master index file (psi_iir_index.xml) that resides in the old registry location. When an existing installation is updated to a later maintenance release or point release, an entry for the installation is created in this file and the registry for the old release is removed.