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I found the following solution but it doesn't apply to Home Premium edition cause you don't have 'secpol.msc':

Disable Admin Approval Mode

Use the following steps to disable Admin Approval Mode.

Note: To perform this procedure, you must be logged into a client computer as a local administrator.

To disable Admin Approval Mode

From the Windows Vista default Start menu, All Programs, Accessories, Run, type secpol.msc in the Run dialog box, and then click OK.
If UAC is currently active, a User Account Control dialog box appears. If so, verify that the details presented match the request you initiated, and then click Continue.
From the Local Security Settings console tree, click Local Policies, and then click Security Options.
Scroll down and double-click User Account Control: Run all administrators in Admin Approval Mode.
In the User Account Control: Run all administrators in Admin Approval Mode Properties dialog box, click Disabled, and then click OK.
Close the Local Security Settings window.
Disable User Account Control from prompting for credentials to install applications

Use the following procedure to disable UAC from prompting for credentials to install applications.

Note: To perform this procedure, you must be logged into a client computer as a local administrator.

To disable UAC from prompting for credentials to install applications

From the Windows Vista default Start menu, All Programs, Accessories, Run, type secpol.msc in the Run dialog box, and then click OK.
From the Local Security Settings console tree, click Local Policies, and then click Security Options.
Scroll down and double-click User Account Control: Detect application installations and prompt for elevation.
From the User Account Control: Detect application installations and prompt for elevation Properties dialog box, click Disabled, and then click OK.
Close the Local Security Settings window.
Change the elevation prompt behavior

Use the following procedure to change the elevation prompt behavior for UAC.

Note: To perform this procedure, you must be logged into a client computer as a local administrator.

To change the elevation prompt behavior

From the Windows Vista default Start menu, click Accessories, click Run, type secpol.msc in the Run dialog box, and then click OK. From the Local Security Settings console tree, click Local Policies, and then Security Options.

Scroll down to and double-click User Account Control: Behavior of the elevation prompt for administrators or User Account Control: Behavior of the elevation prompt for standard users.

From the drop-down menu, select one of the following settings:
No prompt
Prompt for credentials (this setting requires user name and password input before an application or task will run as elevated, and is the default for standard users)
Prompt for consent (this is the default setting for administrators only)
Click OK.
Close the Local Security Settings window.

Note: Information provided in this document is from Microsoft.