Is there a way to disable "check online for updates from windows update" in windows update settings?

Solution 1:

There are settings in the Server 2008/2012 policies that aren't accessible on your 2003 server I believe, such as "Do not connect to any Windows Update Internet locations" under the Computer settings you show above.

I believe the settings you are looking for in a 2003 environment are:

Disable access to Windows Update

The correct policy for v6 operating systems to achieve the desired objective is: Turn off access to all Windows Update features

and is located in Administrative Templates | System | Internet Communication Management | Internet Communication Settings

If this policy setting is enabled, all Windows Update features are removed. It blocks access to the Microsoft Update and Windows Update Web sites, and in Windows Vista will gray out the Check for updates option in the Windows Update application. The machine will not get automatic updates directly from Windows Update or Microsoft Update, but it can still get updates from a WSUS server. This setting overrides the user settings Remove links and access to Windows Update and Remove access to use all Windows Update features. To disable access to Windows Update
1.In the Group Policy Object Editor, expand Computer Configuration, expand Administrative Templates, expand System, expand Internet Communication Management, and then click Internet Communication settings.

2.In the details pane, click Turn off access to all Windows Update features, and click Enabled.

3.Click OK.