Update Existing Installation option is greyed-out while running PTC Solution Installer (PSI) to update Windchill solutions

• Update Existing Installation option is grayed out while running PSI (PTC Solution Installer)
• Update Existing Installation option is grayed out in PSI Windchill 
• Cannot select the Update Existing Installation option to update Windchill solutions
• The migrated Windchill installation (clone Windchill instance from other server) cannot recognize the existing Windchill installation instance
• Update Existing Installation option is not available
• PSI / Select the installation to update step does not show the Windchill instance
• Can't Update Existing Installation
• Is there a way to regenerate PSI folder?
• Windchill 11.0 Platform Structures model option is grayed out
• During the CPS update, Update Existing Installation option is greyed out
• Update Existing Installation option is grayed out in PSI of Windchill 12 
• Getting below error in PSI logs 
• Update Existing Installation is grayed out while Moving Arbortext Content Manager (ACM) to Windchill PDMlink

DEBUG   - Doesn't contain a registry in the standard instalArbortext Content Manager Arbortext Content Manager l registry location.  Trying old location...checking /app/ptc/Windchill_12.0/WindchillDS/codebase/instreg.
DEBUG   - Doesn't contain a registry for this directory.
DEBUG   - No install registry found for 'windchillds'   loadpoint '/app/ptc/Windchill_12.0/WindchillDS'.
Setting as not installed and instance to recoverable.

• Getting the below error in the PSI Installer logs. (Refer to Cause 9 in solution)

Doesn't contain a registry in the standard install registry location.  Trying old location...checking x:\ptc\Windchill_xx.x\Java\codebase\instreg.  DEBUG   - Doesn't contain a registry for this directory.
DEBUG   - No install registry found for 'javasdk'   loadpoint 'x:\ptc\Windchill_xx.x\Java'.  Setting as not installed and instance to recoverable...

• "Update Existing installation" is greyed out when attempting to update existing 12.0.2.x installation to 12.1.0.0
• Updatable is evaluated as false in  PTCSOLNINSTALLER_PtcInstall.log

DEBUG <timestamp> - Setting parser.
DEBUG <timestamp> - InstallPanel.addEmptyPanel()
DEBUG <timestamp> - Processing assembly 'ie', instreg version: 5
DEBUG <timestamp> - Installed ReleaseId:
DEBUG <timestamp> - ie.12.0.20.01.20
DEBUG <timestamp> - Compatible ReleaseId Ranges:
DEBUG <timestamp> - Range 0: ie.12.1.0.00.00 -- ie.12.1.0.99.999
DEBUG <timestamp> - =======================================
DEBUG <timestamp> - Install: <wt_home>\Windchill
DEBUG <timestamp> - ie installed: ? true
DEBUG <timestamp>- Update version check successful: false
DEBUG <timestamp> - Updateable: false
DEBUG <timestamp> - =======================================

• Update existing grayed out when trying to apply CPS from Windchill 13.0.1.3 to 13.0.2.0
• Unable to see the option of " Move up to Windchill PDMLink" after selecting the "Update Existing Installation" option for "Arbortext Content Manager" in the PTC Solution Installer of Windchill PDMlink