As all of you’ll know Windows Vista which is the latest client operating system from Microsoft has many security features. One of these features is the User Account Control (UAC).
When this feature is enabled on a Windows Vista computer, each and every time there is an administrative task been performed such as installing a new program, modifying a system setting etc. a notification window will be popped on to the desktop, briefly locking or disabling the rest of the activities until you verify your action with the administrative credential to continue with the task. This is applicable even if you are logged on to the computer with administrative privileges.
One of the main reasons to have this is to protect your computers from Malware. When a malware is been executed in your computer and when it is about to perform an administrative task you will be notified by this popup requesting for your permission 🙂 (Normally when there is a Malware running on your computer it runs in the background where you won’t notice whether its executing or not until the malware successfully execute and harm our systems).
By default this option is enabled but some of us turn this option off by visiting the User Account section in the control panel or by using msconfig.exe utility. But it’s always recommended and advisable to keep this feature enabled for your own good 🙂
PS: After I installed my Windows Vista Service pack 1 i should say that the performance of my computer has gone up tremendously.