Windows 7 has special protection on some system folders (Windows, Program Files, etc). You can try running Unleashit as administrator (right click the icon, and select "run as administrator"). If the problematic operations work when you run with administrative access, then it's likely that Unleashit wants to save its settings file to the installation directory under Program Files (or Program Files (x86) if you are running Win7 x64). That was a common technique "back in the day," and since Unleashit hasn't been updated since 2004, long before even the release of Windows Vista, this could likely be the source of the problem. It's too bad that the program isn't properly catching an exception like that though!