Windows 8.1 - Disable the UAC (User Account Control)
The UAC made its first appearance on Windows Vista and has been around since then. As an administrator, UAC allows you to define the user privileges. It is quite a formidable tool when there are multiple users using the same PC, but not when you are the sole administrator/user.
To disable the UAC:
Open the Run tab (Windows Key + R).
Type msconfig and press Enter.
Go to the Tools tab > Change UAC settings.
Click on Launch to access the User Account Control Settings dialog.