Uninstall and Reinstall Civ4:
Use Control panel to uninstall Civ4
If still present delete ...\prgram files\firaxis games\sid meier's civilization 4\ manually
Delete "...\documents and settings\<username>\my documents\my games\sid meier's civilization 4" manually
Delete "...\documents and settings\<username>\application data\my games\sid meier's civilization 4" manually
Delete "...\documents and settings\<username>\local settings\application data\my games\sid meier's civilization 4" manually
(note: application data is a hidden directory so you need to configure windows explorer to show hidden files, also these directories in application data are sometimes removed by the uninstall routine)
Delete "...\Program Files\InstallShield Installation Information\{CFBCE791-2D53-4FCE-B3FB-D6E01F4112E8}"
(note: InstallShield Installation Information is a hidden directory so you need to configure windows explorer to show hidden files).
Install Civ4, immediately patch it to 1.61 (download it fresh from
here) then patch it to 1.74 (get it from
here
install the most recent version of DirectX 9c from
Microsoft