Disabling User Account Control (UAC) in Windows Server 2012 & Windows Server 2012 R2 should be simple; open Control Panel -> User Accounts, click on Change User Account Control settings, select Never notify.
The reality is somewhat different. Following the installation of some software, I needed to run a batch file to delete files from multiple drives on a server. Right-clicking the batch file and choosing “Run as Administrator” didn’t delete the files. Double clicking the batch file had the same problem. Disabling UAC through Control Panel didn’t help things.
The answer was to set the HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System EnableLUA registry key to 0x00000000 as per the following MSDN article here. Following a reboot, UAC was completely disabled and the batch file worked correctly.
I’ve also found the registry change was required to enable the Dell 7.3.0.1 patch for Open Manage Server Administrator to install. Without the registry change I was unable to get the patch to install correctly. This included running the patch with UAC enabled and choosing the option to continue when the UAC prompt popped up, and running with UAC disabled via Control Panel.
Richard Skinner 
Thanks, worked correctly.
Thanks. Reboot was not necessary for me.
Thanx a year later still functioning great! And great howto! Reboot was necessary here.
Worked like a charm. Thank you very much!
This worked for most things, but an application developed for Windows XP crashes. The faulting DLL is the Windoze base kernel. Awesome job Mickeysoft.
Very helpful article, resolved my issue
I am logged in as Administrator, but when I go to Control Panel -> User Accounts I don’t see “Change User Account Control”. I see only “change account type: and “remove user accounts”, plus Credential Manager and links under that. So I am at a loss as to how to proceed.
Just above Change User Account Control, click on User Accounts again. You will be able to see.
thank you, it’s working :))