Only one instance of Patch Manager is allowed per Manager Error while trying to Uninstall/Reinstall of Patch Manager component from ISO.

Document ID : KB000115153
Last Modified Date : 17/09/2018
Show Technical Document Details
Issue:
Only one instance of Patch Manager is allowed per Manager Error while trying to Uninstall/Reinstall of Patch Manager component from ISO. 

User-added image
Resolution:
The problem could be in table ca_application_registration If UPM has been uninstalled but this SQL Query returns 1 row :
Run the below query on mdb. 
select * from ca_application_registration where product_code=2035
Execute Below query to remove the row :
delete from ca_application_registration where product_code=2035

Reboot the server and try the installation again