Always a good idea to specify what platform you’re on, as this can greatly affect the answer. For AIX, this is a combination of the /etc/environment file and your .profile. The /etc/environment file should set the CL_INSTALL_DIR environment variable to the last version that you installed. Then in your .profile, there should be a setroot, which will set your root to whatever’s defined in /etc/environment. Could also be that your .profile, or .profile.local.end is set up to specifically set your root to 6.1. So I would check those.
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