How can I enable the Anonymous SID to be part of the Everyone group in Windows XP and later?

A. You can make Anonymous a member of the Everyone group by making the following registry change:

1. Start the registry editor (regedit.exe).
2. Navigate to the HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa registry subkey.
3. Double-click the everyoneincludesanonymous value.
4. Set the value to 1 and click OK.
5. Close the registry editor.

You can also configure this setting via Group Policy. To do so, open the appropriate Group Policy Object (GPO), then expand Computer Configuration, Windows Settings, Security Settings, Local Policies, Security Options. Enable the "Network access: Let Everyone permissions apply to anonymous users" option.