Why doesn't the Deep Freeze screen appear in the SignUp Client installer?

I am installing the SignUp Client on a PC that has Deep Freeze installed. The Pharos Installation and Configuration manual states that when the Pharos installers detect the presence of Deep Freeze, they display a screen that allows me to enter the path to a “safe” location where the SignUp Client can store configuration information, so that it will not be erased on a reboot.

However, when I run the installers, this screen doesn't appear, and I am unable to specify a "safe" location.

The SignUp Client installer checks for the presence of a Deep Freeze system file in order to determine whether or not Deep Freeze is installed on a PC. In newer versions of Deep Freeze, this file is not present in the expected location, so the check fails and the Deep Freeze screen is not displayed.

In this case, you must specify the "safe" location manually after the SignUp Client is installed. Specify the location by editing the registry on the SignUp Client PC. The relevant value is:

HKEY_LOCAL_MACHINE\SOFTWARE\Pharos\SignUp Client\ConfigFileDir