Disabling Vista’s User Account Control (UAC) - Microsoft Windows Tips

User Account Control (UAC) is a feature in Windows Vista that can help prevent unauthorized changes to your computer. UAC does this by asking you for permission or an administrator‌ password before performing actions that could potentially affect your computer's operation or that change settings that affect other users.
UAC will alert you with one of the following messages:

Windows needs your permission to continue

A Windows function or program that can affect other users of this computer needs your permission to start. Make sure to ensure that it's a function or program you want to run.

A program needs your permission to continue
This will happen when a program that's not part of Windows needs your permission to start. It has a valid digital signature indicating its name and its publisher, which helps to ensure that the program is what it claims to be. Make sure that this is a program that you intended to run.

An unidentified program wants access to your computer
This is caused by a program that your administrator has specifically blocked from running on your computer is trying to run. To run this program, you must have an administrator unblock it.

The main reason to use UAC is to prevent malware and spyware from installing or making changes to your computer without your permission. This comes in handy when you have users who may go to inappropriate websites or download software from the Internet that may be of risk to their computer. If you trust your users or if its just you that will be using your computer and you are confident that you will not be installing anything you shouldn’t then you can turn this feature off.

Here is how you turn the User Account Control feature off.

1. Open User Accounts from Control Panel.

2. Click on turn User Account Control on or off.

3. Uncheck the box that says Use User Account Control (UAC) to help protect your computer.

4. Click Ok. You may have to enter administrator credentials depending on who you are logged in as.

5. Restart your computer for the changes to take effect.