In a multi-instance environment, after removing the previous release of Client installation,
when running the setup to reinstall the new release of the Client, it fails with error:
The specified instance is already defined in the CA Workload Automation AE configuration.
Specify another instance.
Release : 11.3.6
Component : CA Workload Automation AE (AutoSys)
The encountered problem was related to the instance file remaining under /etc folder.
# cd /etc
# ls auto*
auto.PRD < =====
After removing the auto.$AUTOSERV file under /etc directory, installation completed successfully.