hum... are u SURE u are installing EB on top of a CLEAN VANILLA version 1.5 or 1.6. IF you have Alexander RTW expansion (or other mods), that might be giving u some issues

IF all else is failing... delete RTW and re-install it again. IF you have RTW BI, ur ok. IF you have the old RTW CD's check the version, u might need to download 1.5 from Activision.com.