This is an Installation Shield Error and it is a result of a corrupted "setup.ini" File The solution is better worded here;
"Based on their responses, this is a translation problem with the setup.exe bootstrapper. In InstallShield 2009, if the "Setup Launcher Type" field (on the "Setup" tab of a release) is set to Unicode, this problem might happen sometimes. Setting the "Setup Launcher Type" to ANSI seems to fix the problem."
If you are running an older version of Installation Shield you might also want to update;
InstallShield - Consumer Central
Hopefully this works for you.