Core issue
This issue occurs if the Symantec AntiVirus runs on the same machine as the Access Control Server (ACS), which can result in an inability to stop the CSAuth service manually.
This is a compatibility issue.
Resolution
In order to resolve this issue, stop the Symantec AntiVirus or any other antivirus service first, and then stop the CSAuth service.
Refer to Cisco Secure ACS for Windows Compatibility for more information.
