Running Windows 7. If I try and install rift from the CD, it won't allow me to install and will give me the option to modify, remove or repair the game. When I try and do any of these processes it says, "error: -1605 This action is only valid for products that are currently installed." When I go to the uninstall tool in control panel and try and uninstall rift, or click the uninstall button on the install menu from the CD, I get error "1628: failed to complete installation". I've tried cleaning my registry, cleaning my temporary files, cleaning duplicate and empty files, uninstalling in safe mode, and a suggestion someone else had said about deactivating an idriver.exe process in the process manager.
So I found a solution and decided to post it to help anyone else who has a similar problem. I had a registry key for the uninstall but no files related to the game, so whenever I tried to install it would see the registry key and assume there was a game installed. I downloaded Ccleaner and cleaned out my registry. Then, in the tools section of Ccleaner I found the rift uninstall selection and selected the delete entry option. This removes the uninstall registry entry but doesn't uninstall the game. If you don't have the game on your computer this isn't a problem.