[HELP] How to repair the versions of the Engine if they were in a different disc

I had the UE4 engines in a separated disc, but since the disc start to fail, i decide to move everything to the main disc while trying to buy a new one, the thing is, how do i reallocated the path? The launcher is still thinking the engines are in disc D: but they are in this C: now, i even make the folders that should go inside the Program Files folder. I try to remove one of the engines and re installed it, and it just pops up an error saying that the installation most be in an empty folder, blocking the install button. How do i fix this?