User Account Control (UAC) can help you prevent unauthorized changes to your computer. It works by prompting you for permission when a task requires administrative rights, such as installing software or changing settings that affect other users.

We don't recommend turning User Account Control off. If you do turn it off, you should turn it back on as soon as possible.

Open User Accounts by clicking the Start button , clicking Control Panel, clicking User Accounts and Family Safety (or clicking User Accounts, if you are connected to a network domain), and then clicking User Accounts.

Click Turn User Account Control on or off. If you are prompted for an administrator password or confirmation, type the password or provide confirmation.

Select the Use User Account Control (UAC) to help protect your computer check box to turn on UAC, or clear the check box to turn off UAC, and then click OK.

Sometimes it´s not possible to uninstall avast! the standard way - using the ADD/REMOVE PROGRAMS in control panel. In this case, you can use our uninstallation utility aswClear.

1. Download aswClear5.exe on your desktop. (Use this link for download: http://files.avast.com/files/eng/aswclear5.exe)
2. Start Windows in Safe Mode
3. Open (execute) the uninstall utility
4. If you installed avast! in a different folder than the default, browse for it. (Note: Be careful! The content of any folder you choose will be deleted!)
5. Click REMOVE
6. Restart your computer.