I found the following web site with the settings to change in Group Policy.
They worked for me.

[url]http://blogs.msdn.com/wndp/[/url]

"Steve Foster [SBS MVP]" wrote:
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> Mike Dewdney wrote:
>[color=green]
> >The Network Map screen reports "Mapping is disabled by the group policy".
> >The Vista machine is a member of a 2003 domain. What GPO would control
> >this?[/color]
>
> Try here:
>
> [url]http://www.microsoft.com/technet/windowsvista/library/gpol/a8366c42-6373-48cd-9d11-2510580e4817.mspx?mfr=true[/url]
>
> I'd hazard a guess that this falls under the Network Location Awareness
> stuff.
>
> --
> Steve Foster [SBS MVP]
> ---------------------------------------
> MVPs do not work for Microsoft. Please reply only to the newsgroups.
>[/color]