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Badbad thingy in vista/win7
Happens when installing in default location (program files)
I disabled it 119 years ago, so I dont remember if it can be overridden with an Administrator permission.
But dont change original files (even with a backup). Instead make a small mod. Its not difficult at all. There are many guides in the forum to teach you how, but basically you just need a folder in the Mods folder of beyond the sword. (the one with Afterworld, Broken Star, Charlemagne and other default mods).
(Default path : C:/Program Files/Firaxis Games/Sid Meier's Civilization 4/Beyond the Sword/Mods)
inside that folder you put the folders and files you need. Take a look at another mod to see how, but in this case you need :
CIV4WorldInfo.xml inside
...Civilization 4\Beyond the Sword\Mods\[name of your mod]\
Assets\XML\GameInfo
and vupti. You have made your first mod. simple as that. you then have to load it from the
advanced menu - load a mod in the main menu or you can make a shortcut of BtS and in destination field write mod=\[name of your mod]
example
"C:\Games\Civilization 4\Beyond the Sword\Civ4BeyondSword.exe" mod=\VIP