Please check the folder again:
There should be a Civ4.ini, and a Civ4.ini.bak. In case your windows is set to hide the known file extensions, then you've edited by accident the .ini.bak, and not the .ini file.
There should be a Civ4.ini, and a Civ4.ini.bak. In case your windows is set to hide the known file extensions, then you've edited by accident the .ini.bak, and not the .ini file.