I have a problem with Vista, WMP11 media sharing to a Sony Playstation 3.

When I have the PS3 search for a media player, Vista initiates a search for
a Public Network and turns off Network Discovery.  As a result, the PS3
cannot find a media server.

I have a Gateway notebook running Vista Premium with all Windows updates
installed that was purchased in January, 2007.  I have correctly configured
my computer for DLNA media sharing.  Media Sharing "Default Settings have
been chosen which allow for the sharing of all media. In WMP11, all media has
been added to the "Library" for sharing.

All required WMP11, network sharing and UPnP services are started
automatically and IPSEC is OFF and set for manual starting . I have
configured my Linksys wireless router to have the required open ports in
“Port Forwarding,” I have checked McAfee firewall to allow WMP11 media
sharing, and I have set the Windows firewall to allow "Network Discovery," as
seen in the "Network and Sharing Center" window.  In managing my wireless
networks, I have merged or eliminated all wireless networks except for my
"Private Network."

The Computer recognizes the PS3 as an "Unknown Device" in the "Media
Sharing" window, which I have "Allowed" to share media in my "Private
Network."

I then open the "Network and Sharing Center" window which displays my
"Private Network" and "Network Discovery” is turned ON under "Sharing and
Discovery."

When I have the PS3 "search for a media server," the PS3 usually reports
that it "cannot find a media server."

If I then look at the "Network and Sharing Center" window, Vista, for some
unknown reason, changes from my "Private Network" setting, and begins
searching for a "Public Network."  When it does this, Vista turns OFF
"Network Discovery," which causes the PS3 to fail to find the media server
(WMP11).

After Vista fails to find a "Public Network," it returns to the "Private
Network" and "Network Discovery" usually is turned back ON, but the PS3's
search for a media player has failed. This also occurs when both the Vista
and McAfee firewalls are turned OFF as well, so it should not be a firewall
problem.

Occasionally, the PS3 actually locates a media server (WMP11).  Sometimes
the folders are empty or partially missing.  And occasionally, all of the
media is actually there.

Does anyone else have this problem with Vista, and does anyone have a
solution as to how to stop Vista from searching for a "Public Network”, and
turning OFF "Network Discovery” when the PS3 searches for a media server???"