Unable to run certain apps even though I am an administrator

I am having problems running some apps in my laptop. This happens when I install apps to my C://Users//Rahul mukherji folder. I don't see any problems during the install. For example, I installed the Eclipse IDE, however some features didn't work because of access being denied. I managed to reinstall it and make it work, but now Android Studio is not starting, because access is denied to some file in C://Users://Rahul mukherji. I am fairly certain this is a permissions problem, and so how do I resolve it?

(Also, is there any way to rename my User folder? The "mukherji" is because the guy who set the laptop up made a typo.)

By all means keep the original downloaded executable/MSI installer files in your user folder (so you can re-install them again at a later date). However when you install the programs, install them to the following locations:

32-bit applications - C:\Program Files (x86)\
64-bit applications - C:\Program Files\

The reason I say this is that when I reinstalled Android Studio, a warning was given that having whitespace in the project folder can cause problems (the User folder is C://Users://Rahul mukherji) So I really need to fix this.