When the BCAAA service is stopped, the Windows API, TerminateProcess, is called to forcefully terminate all bcaaa-xxx.exe instances.
However, it is possible that the target process, bcaaa-xxx.exe, can not be terminated. This usually happens if the bcaaa-xxx.exe's thread is stuck in a syscall. An example would be the LDAP Simple Bind function that makes call to Winsock. In this case, the old SSO instance of bcaaa-xxx.exe will eventually notice that its parent bcaaa.exe process has gone away and terminate on its own. Alternatively, you can manually kill the bcaaa-xxx.exe process.
If the bcaaa-xxx.exe process is not terminated after an extended period of time, this may indicate potential issues and a case should be logged with Blue Coat Systems.
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