Ok folks, i recently realised my DX9c is corrupted and is resulting in lower than normal performance in DX9 compliant games. Getting much lower fps than i should in Everquest 2. So, thing is whenever i try to reinstall DX9 it says 'the components are already installed and ready to use' and there is nothing i can do to get it to install 'over' my previous installation. I've even tried installing DX9b to see if i can 'roll' back. Any suggestions on how i can install DX9c over the current installation?