I have no idea if I'm doing something wrong or if there is away to fix it. I decided to play the game after quite ahiel of not playing. I installed a second hardrive after i'd played last. Whne i need to switch disks the game insists i place the disk in drive D which of course is my hardrive. If anyone knwos how i can remedy this problem i'd be quite appreciative. I really do not want to start the game over if at all possible.

You could always reinstall the game. Do not worry, if you uninstall the game and install it again the save files will not be touched. If you decide to do this Just beckup the save files before (just in case)

IIRC, some of the .ini files contains path to your CD drive. Edit the .ini file so that it will contain the correct drive letter of your CD after installing the second HD.

i would recommend uninstalling the game and backing up the saves as ctenas suggested...
your computer is still looking for your 'partial install' on your old drive - with your new one you should have the room to accomplish a 'full install' which will prevent the harassment of having to switch disks mid-game anyway...
out with the old...