There are many people who complain that even though they have User Account Control (UAC) turned off, their actions still require administrator permission.
These users were Windows 8 or 8.1 users who had turned off UAC by the 'easy' method (that is, going to control panel > all control panel items > action center > change user account settings and then sliding the slider all the way down).
In earlier versions of Windows, sliding the slider all the way down would essentially mean turning off UAC completely, but in the newer versions of Windows, doing so just puts UAC into 'silent mode', which prevents the UAC dialogs from appearing, but UAC is still enabled.
BUT, there's still a way to completely disable UAC in the newer versions of Windows. You need to modify the Windows Registry to do it.
WARNING: Before you do it, let me warn you that if you perform the following steps, you will no longer be able to open any Metro applications! Also, turning off UAC completely makes your computer vulnerable to a variety of threats. I would not recommend doing this unless you undoubtedly know what you're doing.
1. You need to open the windows registry editor. Press [Windows Key + R] to open Run. Then type in 'regedit' (without quotes) and hit enter.
2. Navigate to this key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System
3. In the right pane, look for EnableLUA.
4. Double click on it.
5. Change its value to 0.
6. Hit Enter.
7. Close regedit.
8. Reboot your machine. WARNING: If you have 'Hybrid Boot' enabled (most users usually do), DON'T shut down and then re-open your computer. Best thing to do is to press [Windows Key + X], then press [U] and finally press [R]. Remember to save your files and close all applications before doing this.
All done. Now you have completely disabled UAC.
If you ever wish to enable UAC again, just follow the same steps and on step 5, change the value to '1' instead of '0'.
EDIT: Minor edits and added images.
Edited by awesomearc, 25 December 2015 - 10:20 AM.