I have a problem with both KOTORs (I and II) I recently ran into trouble with them, I don't think they are related to each other. I've been messing around alot with them lately with all these fun mods and stuff. I was having some different problems with them and instead of just asking the wise geniuses here I tried to just solve all the problems at once by just deleting and reinstalling them.
:( Didn't work, I'm pretty sure I deleted everything could find, but the add-remove programs tool shows that theres still something(I can't figure out what) left, I can't find any access to get rid of these files and when I try to just use the add-remove tool to delete them it locks up. If I try to just go ahead and re-install the games they (because there is still something left I guess) only let me uninstall which also locks up. There doesn't seem to be any option to install and overwrite anything.
So now I'm stuck with no Knights, and my modding education has been seriously delayed.

Has anyone else had this problem when reinstalling.

to overcome this problem, your going to have to remove the registry keys for the games from the registry.

to do so, goto your start menu and hit "Run". then type "regedit" into the field and press enter. this will open up Windows Registry Editor.

**Warning: Do not mess around with anything other than the registry keys for the Kotor games. Otherwise, you could seriously mess up your computer.**

now, expand "HKEY_LOCAL_MACHINE", then expand "SOFTWARE". scroll down until you find "LucasArts", expand that. from there, just click on the "KotOR" file and press delete on your keyboard.

the one for Kotor II should be named KotOR2, and if you need to, you can delete that one as well.

this should solve your problem since the game is looking for the registry key to check for the installation. even if you don't delete the one file that was left-over, Windows won't even recognize it anymore, so the game should be able to install from their. :)