Wrong Drive Instalation

I installed a program a few days ago (Micro Measure) Just used it to take a few pictures but then could not find the pictures it took. The program has installed on my C: drive just like it said but it is saving all the pictures to my external Hard Drive. That's No good it is not always connected to that PC and i don't want it saving thing there by default anyway, i can change it to save in my pictures folder on C: but it makes me do it every time for every picture.so i uninstalled the program,used a disk cleaner and registry cleaner unplugged the external Hard Drive.Tried to install the Program again and now it is telling me that H: is an invalid drive.(H: is what the external hard drive was labeled when it was connected) Since then i have tried a couple of times,i have tried it with the drive unplugged as i said,i have tried it disabled even connected it uninstalled the external hard drive unplugged it rebooted and still this program will not install again unless i put the external drive back on.It must have saved some information somewhere but i cant track it down and delete it. I'm guessing it must be in the registry somewhere. Does anyone know how i can override this because when it says H: is invalid drive the only option is to exit.

Welcome
Go back prior to the install with system restore. http://www.vistax64.com/tutorials/76905-system-restore-how.html

I'm looking for someone with a little more than basic knowledge and who will not just state the obvious. I should have said i did that in my question but sorry,i thought it went without saying.