If your installer file does not have an .msi extension, it needs to choose or allow the user to choose the installation directory. After the new directory is chosen, your installer needs to update the .atc file type association in the registry so that the thin client can locate the newly installed executable after your installer finishes. If you want to install the thin client in a directory relative to the location of the existing thin client, you can determine the location by querying the registry entries for the .atc (or .acutc) file type association.
The thin client examines the .atc file type association in the registry by first reading the value of HKEY_CLASSES_ROOT\.atc to identify the version-specific name of the current thin client. It then reads the value of HKEY_CLASSES_ROOT\<current_version>\shell\open\command to get the absolute directory path to the acuthin.exe executable.
For example, after a Version 7.2 thin client installation, HKEY_CLASSES_ROOT\.atc has the value
MicroFocus.ThinClient.72
HKEY_CLASSES_ROOT\MicroFocus.ThinClient.72\shell\open\command may have the value
"C:\Program Files\AcuThin\acuthin.exe" "%1"
This value starts with the absolute directory path for the thin client. Your installer should change this value if you install the new thin client in a different directory.
If the value of TC_INSTALLER_CLIENT_FILE is an executable (.exe file), the thin client uses the value of the TC_INSTALLER_ARGS configuration variable as the command-line options passed to that executable. For example, if you want msiexec.exe to log all of its operations to a file named msi.log, you could set TC_INSTALLER_ARGS to "/log msi.log". (See the Microsoft Windows Installer documentation for more details.) TC_INSTALLER_ARGS has no default value.
Note that if the TC_INSTALLER_ARGS configuration variable is set, the TC_INSTALLER_UI_LEVEL configuration variable is ignored. See Microsoft Windows Installer for more information.