Both local and remote servers are Windows 2003 SBS SP1. Both have an
internal DNS. There was only one A record for the Vista machine in
the local server's DNS. Note that this problem also occured with
Vista RC1. It's the reason I gave up using it.

On Mar 7, 9:34 pm, "Robert L [MVP - Networking]" <nore...@hotmail.com>
wrote:
> Is the windows 2003 server or SBS? Do you have an internal DNS? If yes, check the DNS record. Do you have the DC registers two A records?
>
> Bob Lin, MS-MVP, MCSE & CNE
> Networking, Internet, Routing, VPN Troubleshooting onhttp://www.ChicagoTech.net
> How to Setup Windows, Network, VPN & Remote Access onhttp://www.HowToNetworking.com <t_ja...@yahoo.com> wrote in messagenews:1173314914.640840.112420@64g2000cwx.go oglegroups.com...
>
> Yes, both the remote and local servers are DCs (they're WinSBS's), but
> I fail to see how that has anything to do with it. The problem occurs
> with Vista but not with other XP clients (both are in the same
> environment on the client's local domain). In fact if I boot up one
> of my desktops with XP, the problem does not occur but if I boot the
> *same* desktop computer up with Vista (via a 2nd HDD), the problem
> does occur.
>
> On Mar 7, 11:33 am, "Robert L [MVP - Networking]" <nore...@hotmail.com> wrote:
>
> > Is the server also DC? The VPN may create a virtual multihomed server so that the server have a name resolution. These search results may help,
> >
> > Name resolution on VPN
> > That reason is that VPN server is a Virtual Multihomed Server. The resolution is to disable NetBIOS Over TCP/IP and DNS register on all interfaces including ...
> > http://www.chicagotech.net/nameresolutionpnvpn.htm-
> >
> > windows vpn as a router
> > Connectivity issue after enabling VPN in multihomed server ... After you configure the RRAS as a virtual private network (VPN) server in Windows 2000 Server ...
> > http://www.chicagotech.net/vpnasrouter.htm
> >
> > Bob Lin, MS-MVP, MCSE & CNE
> > Networking, Internet, Routing, VPN Troubleshooting onhttp://www.ChicagoTech.net
> > How to Setup Windows, Network, VPN & Remote Access onhttp://www.HowToNetworking.com <t_ja...@yahoo.com> wrote in messagenews:1173248408.904485.7390@64g2000cwx.goog legroups.com...
> >
> > Has anyone else come across this yet? When I connect to a Win2003
> > server across the public internet via a Vista PPTP VPN client, after
> > several hours (or days) of leaving the connection active, connectivity
> > to my network shares (on a local Win2003 server) is lost. This
> > doesn't happen with the Windows XP VPN client in the same environment.