I recently had a software installation problem when I recently upgraded my SATA drive on my current computer. Instead of the main drive reading C, which is standard for most computers. My computer choose E drive as it's home drive. There is nothing wrong with having E drive as your home computer, except some software's are programed to excute and install on the current C drive. Making installations fail or almost impossible. One way to fix this is to go to the Control Panel -> Administrative Tools -> Computer Mangement -> Disk Mangement. All you need to do is change the drive letter to another drive and move the current C drive to another destination drive that doesn't conflict. If you do everything right there should be no C drive when you open My Computer.
Now to substitute the C drive so that you can install the current program that's looking for the C main drive. All you have to do is to go to Start -> Run -> type CMD and Enter. This will open up DOS and in DOS you just type the following:
subst c: e:\
(in which e is the current main drive that windows is booting up on your computer)
